Mutation breeding

With the inevitable risk posed by global climate change to crop yield and ever increasing demands
of agricultural production, crop improvement techniques have to be more precise in developing
smart crop varieties. This review reviews the past, current progress and assesses the future
directions in mutation breeding for crop improvement. It provides a background to plant mutation
breeding strategies, basic and advanced techniques, and provides a critical review of this
approach in comparison to other methods for the genetic improvement of crops. Mutation
breeding is a fundamental and highly successful tool in the global efforts of agriculture to feed an
ever increasing and nutritionally demanding human population. The physical and chemical
mutagens, their effects and their utility are discussed. The induction of mutations has been used to
enhance the yield, better nutritional quality and wider adaptability of world’s most important crops
such as wheat, rice, pulses, millets and oilseeds. The total area covered by commercially
released mutant cultivars clearly indicates that they have played a significant role in solving
food and nutritional security problems in many countries. Of all the mutant varieties developed,
majority of mutants were produced through direct mutagenesis of the plant propagules, and alsothere are several reports of mutants derived by irradiating rooted stem cuttings, which paves the
way for in vitro mutagenesis. The production of mutants by irradiation of in vitro cultured tissues
provides a means to treat large populations which would not have been possible before. The
accessibility of genomics information in the public domain combined with the recent advances in
molecular biology techniques have paved the way for transforming old mutation techniques into the
state of art technology for crop improvement and basic genomic research. The molecular tagging
and molecular marker based identification shall bring new dimensions in gene technology. These
would finally lead to rapid enhancement of crops with improved yield, increased biotic and abiotic
stress and reduced agronomic inputs. Thus mutation assisted plant breeding will play a crucial
role in the generation of designer crop varieties to address the threats of global climate change and
challenges of world food insecurity.

Mutation breeding techniques have contributed immensely to crop improvement, by developing and officially releasing thousands of improved crop varieties. In mutation breeding, various physical mutagens such as gamma rays, X-rays, and fast neutrons, and chemical mutagens such as EMS (ethyl methanesulfonate), MMS (methyl methanesulfonate), hydrazine hydrates and sodium azides, were employed. The sudden heritable change in the genetic constitution of an organism not caused by the normal process of genetic segregation is referred to as a mutation. Mutations are the ultimate source of variation in living organisms on planet earth. The knowledge of mutations in higher plants traces back to as early as 1590, however, the application of mutations for crop improvement has a history of eight decades only. Natural mutations occur spontaneously, however, the frequency is very low and inaccessible to Chapter 1 2 plant breeders. The low frequency necessitates the induction of artificial mutation through the use of agents capable of bringing new and heritable variations in the plant genomes. Based on the type of mutations induced, mutagens are classified into several classes, viz., physical mutagens that induce gross chromosomal breakages, chemical mutagens that are known to cause point gene mutations and biological agents that are able to disrupt the functional elements of genes thereby inducing a wide range of mutations. The use of mutagens has resulted in several thousand mutant varieties that have improved characters in more than two hundred fifty plant species across the globe. However, the maximum number of mutant varieties has been induced by physical mutagens followed by chemical and biological agents. This chapter briefly provide insights into the basis of the classification of mutagens, mode of mutagenic action, characteristic features of different mutagens.

Induced mutagenesis generates macromolecular variations which ultimately alters the bio-physiological and morphological nature of the crop genotypes. In the present study, molecular characterization of six high yielding lentil mutant lines, developed from hydrazine hydrates (HZ) and gamma rays mutagen-esis, was carried out with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and random amplified polymorphic DNA (RAPD) markers. Activity of nitrate reductase (NR) and content of chlorophyll and carotenoid were found to be significantly high in the mutant lines. Protein and mineral (Fe, Zn & Cu) contents were also increased considerably in the mutant lines compared to their respective parent genotypes. SDS-PAGE profile of seed storage proteins showed 35 unique bands with 97.14% polymorphism. Genetic divergence analysis generated total 41 reproducible RAPD bands with average calculated polymorphic percentage of 63.06%. Among the primers, OPA-10 showed the highest polymor-phism with significant PIC value. Genetic divergent analysis revealed that genome of cultivar DPL 62 mutated relatively more than the cultivar Pant L 406 due to the mutagen treatments, while DPL 62-B and Pant L406-A were the most divergent mutants induced in the present study. Biochemical and molecular profile of the induced mutant lines facilitates a basis for future conservation and utilization strategies to widen the genetic base of the current lentil breeding population.

Yam,  Dioscorea esculenta which is a high value commodity is a threatened species in Ghana, due to several factors including neglect on the part of science, technology, research and development. Different doses of radiation were use to improve the size and market value of D. esculenta to promote it effective use and enhance effective conservation. We observed through repeated experiments that irradiation of yam planting material at 40 Gy gave the best results producing a M1 generation with a decreased number of tubers but with an increased tuber size per vine. Some yam characteristics are valued more than others, and prices vary across species, time, and market sites. Tuber weight exhibits an increasing marginal value and price per kilogram increases above an optimum size; therefore, yam producers and dealers derive additional reward from extra-large tubers. We conclude that, to effectively access and benefit from urban markets, producers should focus on the improved size and conical shaped-tubers, which are easy to process and meet the aesthetic qualities preferred by urban consumers. The implications for research on improved variety development to reduce poverty and for crop and resource management practices are drawn

particularly in Africa and South-East Asia. The leaves contain high levels of vitamins (especially A, B and C), mineral fibres (such as iron,
calcium and phosphorus), carbohydrates and proteins. They also contain phenolics and alkaloids, such as nicotine, quinine, cocaine, and
morphine, which are known for their medicinal attributes. With the realization of their high nutritional, medicinal and health benefits, the
demand for these vegetables has been on a rapid and steady rise in the recent years. However, due to very low leaf yields that are
considered uneconomical compared to other high-yielding and high-value horticultural crops, production of these vegetables remains on a
small scale. Prolific early flowering and excessive fruit- and seed-set, which compete with leaf production, are the main limiting factors
on leaf yields. To eliminate or reduce fruit-set, hence competition with leaves, induction of male-sterility is probably one of the most
immediate options. The main challenge that faces this strategy is propagation and maintenance of male-sterile lines. This review focuses
on the mutation breeding for improved leaf yields of African nightshades with special reference to male-sterility. Aspects of propagation
and maintenance of male-sterile lines are discussed

An investigation was carried out at the Department of Horticulture college of Agriculture Parbhani during 2016-2018 on the studies on mutation breeding in tuberose (polyanthus tuberosa L.) was studied and isolation of promising mutants were done.The experimental material Phule Rajani of tuberose variety treated with five doses 0.5Kr,1Kr,1.5Kr, 2.0Kr,2.5Kr along with untreated sample (control).in generation VM 1. Results indicated that the mutagenic treatment at lower doses had significant stimulative effect on some parameters that is,sprouting percentage,, Leaf length,Chlorophyll content, rachis length, spike length, number of opened florets whereas most of parameters had showed decreased at desired level content.that is number of days for bulb sprouting,survival percentage, plant height, Leaf area, stem diameter,number of unopened florets,weight of flower.Higher doses of all mutagen were detrimental for growth parameters.and lower doses of mutagen were beneficial for quality parameters seven mutants obtained in VM 1 generation.In

In the current scenario of sky high population and widespread food insecurity, there is an urgent need for productivity improvement of major crops like pulses, one of the most climate friendly and accessible foods for the large poor population of the world. Chickpea is an important pulse crop, having high percentage of nutritional content and is widely used as food across the world. Induced mutagenesis has proved over time as a coherent tool for modern plant breeders to improve the productivity for combating the food insecurity and malnutrition across the globe. Dry and healthy seeds of Cicer arietinum L. var. C-235 were treated with individual and combination doses of gamma rays, sodium azide and hydrazine hydrate to raise the M1 generation. M2 seeds harvested from M1 plants were sown in the nest season. Bio-physiological study in M1 generation showed growth inhibition in the order viz. combination treatment>hydrazine hydrate>gamma rays>sodium azide. In M2 generation, comparative observations were recorded for morphological variation and quantitative traits to assess the genetic response of the chickpea variety C-235 toward the different concentrations of mutagens. Observations on isolated mutants in M2 generation revealed that 0.3% HZ + 0.02% SA was most mutagenic while 200 Gy, 0.03% SA and 0.2% HZ were highest in their individual treatment groups. In context to the frequency of morphological mutants studied in M2 generation, dwarf mutants were found to be highest followed by tall and branching pattern mutants. Highly significant correlation coefficient between yield and other traits showed that the selection for high yielding mutants can be done on the basis of these traits undoubtedly.

Mutagenesis using gamma irradiation is one way of creating variation for selection of useful mutants. This type of variability helps in the selection of desirable traits in terms of growth, total grain yield and nutritional characteristics. The study is an ongoing mutagenesis work which started in 2013 in the Department of Agronomy of UDS Nyankpala campus. The results since 2013 indicated that promising mutant lines have been produced. The mutant lines were obtained through irradiation of seeds of soybeans with 150 Gy, 200 Gy, 250 Gy and 300 Gy doses of the gamma rays. Thus, in the 2016 cropping season, these mutant lines were evaluated in multi locational trials in the various agro ecological zones of Ghana. The mutant lines (treatment) including some un-irradiated control (0 Gy) were replicated three times in randomized complete block design in the field. Results of evaluation of the mutants in the Guinea savanna agroecology  (present study) show that it is possible to effectively increase grain yield at doses of 200 Gy and 250 Gy mutant lines.

Faba bean is one of the most important grain legumes in the world because of its multiple
uses and its ability to grow over a wide range of climatic conditions. The objective of this
study was to evaluate the effectiveness and efficiency of single and combination doses of
gamma rays and ethyl methanesulphonate (EMS) on two different varieties of faba bean.
Studies on induced mutagenesis in faba bean involving EMS and gamma rays are sparse.
Genetically pure, uniform, dry and dormant seeds of Vicia faba varieties Vikrant and PRT-12
were treated with four different doses of gamma rays (100, 200, 300 and 400 Gy) and of EMS
(0.01, 0.02, 0.03 and 0.04%). However, the utility of a mutagenic agent is determined by its
ability to induce a high frequency of desirable mutations as compared to undesirable ones;
thus, it is necessary to assess the effectiveness and efficacy of mutagens. The results indicated
that EMS is more effective in inducing mutations than gamma rays, with the following trend:
EMS > gamma rays+EMS > gamma rays. However, with regard to mutagenic efficiency
measured based on seedling injury, gamma rays were more efficient than EMS, with the
following trend: gamma rays > gamma rays+EMS > EMS. Both mutagenic effectiveness and
efficiency were found to be higher at lower doses of both the mutagens. The possible reason
for decrease in mutagenic efficiency and effectiveness with increase in dose may be the
higher dose of mutagens and less damaging effect of lower doses of mutagens.

Pakistan is well known for its basmati rice with long grain and aroma, as well as for non-basmati indica varieties; however average yield is lower as compared with other countries. Besides, cultural practices, the main reason for low productivity in Pakistan is that, local varieties are susceptible to different biotic and abiotic factors like insect pests, diseases, drought, and salinity. Different approaches have been undertaken in Pakistan to tackle these problems through traditional breeding of selection and crossing, mutation breeding, somaclonal variation as well as plant transformation studies in recent past. For variety development, the most successful examples arose from traditional breeding that produced famous basmati varieties like Basmati 370, Basmati 385 and Super basmati, and non-basmati varieties such as IRRI-6, DR-82, DR-83, DR-92, Swat-I and Swat-II, which earn a significant share of foreign exchange every year. Six varieties have also been developed through mutation breeding, and one through exploitation of somaclonal variation but their contribution to the national economy is not significant. On the other hand, no variety has been registered as commercial by plant transformation groups. This review discusses the problems and prospects of rice breeding with special emphasis on basmati rice in Pakistan particularly in Pakistani Punjab (a major producing area), as well as focuses on future research programs.

The importance of agricultural innovations for raising the living standards of farmers has received substantial attention from the economic and political communities. In Ghana, cassava serves as an important source of calorie and cash crop. Production constraints such as the cassava mosaic disease caused by virus have limit farmers access to productivity potentials and marketing. Breeding efforts attempting to address this constraints have had some success such as the mutant Tech Bankye virus resistant variety. This research, therefore, analysed the impact of some production input on mutant cassava productivity growth in Ghana with the use of Cobb-Douglas production function. Results show that farmers cultivate the mutant variety in addition to other traditional varieties to averse risking in marketing and income. The average cost of production of the mutant variety is higher compared to that of the traditional variety. Eighty percent of the farmers complained difficulty in accessing market for the mutant variety because it could not replace the traditional variety in terms of its texture for the local native “fufu” production and “ampesi” and also deteriorate quickly in storage. However, for industrial production of “gari” and starch, the mutant is the best. Both the mutant cassava and the traditional varieties showed increasing returns to scale, however, the returns to scale of the mutant variety were lower compared to that of the traditional variety. Also, the opportunity  cost of forgoing the traditional varieties to cultivating the mutant variety was very high making adopted farmers hesitant to continue it cultivation.

Wheat (Triticum aestivum L) is the second largest contributor to food security in Kenya. However, water deficiency retards plant growth and productivity significantly. With few drought tolerant varieties available, there is need to develop more drought tolerant wheat varieties. Objective of this study was to screen for drought tolerance in the mutant wheat lines at seedling stage. Seeds of two wheat varieties were subjected to gamma radiation at an irradiation dose of 300 gy (gray). The mutants and two local varieties – Chozi and Duma (controls) were sown in polythene bags in a complete randomized design and screened for various seedling traits. Data were analysed using ANOVA and Pearson correlation. Results indicated that Mutant 1 and Mutant 2 had high emergence percentage, emergence index, energy emergence and per cent seedling recovery compared to local varieties Chozi and Duma. Emergency percentage showed a positive correlation with the following parameters; emergence index (r = 0.965); Energy of emergency (r = 0.990) and Percentage seedling recovery (r = 0.941). It was recommended that the mutant wheat be screened for other biotic and abiotic stresses that affect wheat production in Kenya.

The seeds of Hyacinth bean (Lablab purpureus L.) Sweet varieties Konkan bhushan and Konkan Wal-2 were treated with various doses of chemical (EMS-0.05%, 0.10%, 0.15% and SA-0.010%, 0.015%, 0.020%) and physical (Gamma rays-5KR, 10KR, 15KR) mutagen and were sown in the field with control and harvested in bulk to raise M1 generation to observe the characters and number of mutants in each population. to observe the chlorophyll mutation and leaf morphology. Chlorophyll mutation frequency was calculated on the basis of plant population. A distinct range of chlorophyll and morphological mutants were observed in the M1 generations. Four different types of spectrum of chlorophyll mutant's viz. albina, xantha, viridis and chlorina were identified in the treated population. Various morphological aberrations had been observe viz. Bilobed leaf, reduction in size of leaves, cotton shape leaf, obtuse and retuse apex, notch at margin, sinuate leaf margin, lanceolate leaf, wrinkled leaflet and triforked leaf. The frequency of leaf morphological changes noticed more in SA (0.020%) in Konkan bhushan and EMS (0.15%) in Konkan Wal-2 of Hyacinth bean variety.

Genetic divergence determine in thirty six genotypes of Indian mustard [Brassica juncea (L.) Czern & Coss.] by applying D2 statistics for ten characters facilitate grouping of all the genotypes into eleven clusters. Days to 50% flowering, plant height, days to maturity, siliqua on main shoot, total no of siliqua per plant, no of seed per siliqua, seed yield, biological yield per plant, test weight, harvest index were the main contributors for genetic diversity among the genotypes. Out of 11 clusters, cluster I is used to be the most important comprising 11 genotypes pursuing by cluster IV consisting of seven genotypes, cluster II and V have 5 genotypes, cluster VIII has 2 genotype whereas, rest have single genotypes each. The cluster V presented maximum intra-cluster distance (8.20), while maximum inter-cluster distance was detected between cluster XI and VI (41.82).

In the present study, induction of genetic variability in in vitro regenerated Polianthes tuberosa was observed in the local cultivar, with five different doses of gamma radiations (10, 20, 30, 40 and 50 Gy). No significant differences were observed in the survival rates among the untreated (control) and treated plants with different doses of gamma irradiation. But significant differences were recorded in the plant morphological characters upon gamma radiation treatment of 30 Gy in terms of plant height, number of leaves, leaf size and colour as compared to the control plant.

Genetic divergence determine in thirty six genotypes of Indian mustard [Brassica juncea (L.) Czern & Coss.] by applying D 2 statistics for ten characters facilitate grouping of all the genotypes into eleven clusters. Days to 50% flowering, plant height, days to maturity, siliqua on main shoot, total no of siliqua per plant, no of seed per siliqua, seed yield, biological yield per plant, test weight, harvest index were the main contributors for genetic diversity among the genotypes. Out of 11 clusters, cluster I is used to be the most important comprising 11 genotypes pursuing by cluster IV consisting of seven genotypes, cluster II and V have 5 genotypes, cluster VIII has 2 genotype whereas, rest have single genotypes each. The cluster V presented maximum intra-cluster distance (8.20), while maximum inter-cluster distance was detected between cluster XI and VI (41.82).

A research was conducted to study the effectivity of Test Day records using a Fixed Regression model for genetic evaluation of dairy cattle. The data were collected from first and second lactations of Frisian Holstein dairy cattle from 1989 to 2000 at PT Taurus Dairy Farm Sukabumi. A total of 7503 Test Day records recorded from 456 cows, 40 sires and 342 dams were collected. Variance components were estimated using the animal model with REML and Breeding Values were predicted using BLUP. The results showed that the peak of lactation was reached on day 35. Season was not clearly affecting Test Day. The genetic variance decreased along with the addition of the Test Day in 2 nd lactation up to test 3, and then decreased gradually up to the end of test. The estimation of heritability followed the same patern as the genetic variance. Genetic evaluation based on first lactation plus the first test and second lactation was sufficient for the evaluation of animals, while bulls should be prolonged up to the first three tests. Sari Penelitian ini bertujuan untuk mempelajari efektivitas catatan Test Day dengan model regresi tetap untuk evaluasi genetik produksi susu pada sapi perah berdasarkan laktasi satu dan dua. Data produksi susu berasaldari sapi perah Frisian Holstein periode laktasi satu dan dua dari tahun 1989-2000 di PT. Taurus Dairy Farm Sukabumi. Catatan Test Day sebanyak 7503 buah berasal dari 456 ekor sapi betina, 40 pejantan dan 342 ekor induk. Model yang digunakan adalah Model Regresi Tetap, varian komponen diduga dengan Animal Model dengan Restricted Maximum Likelihood (REML) dan Nilai Pemuliaan dengan Best Linier Unbiased Prediction (BLUP). Hasil analisis menunjukan hasil test ke-35 (TD2) merupakan puncak produksi. Pengaruh musim terhadap produksi susu Test Day mempunyai pola yang kurang jelas. Ragam genetik aditif pada laktasi dua menurun sejalan dengan penambahan catatan Test Day sampai dengan Test Day ke-3, setelah itu meningkat sampai akhir laktasi. Dugaan nilai heritabilitas mengikuti pola yang sama dengan ragam genetik. Evaluasi genetik berdasarkan laktasi satu penuh yang ditambah dengan satu catatan Test Day pada laktasi dua sudah cukup untuk mengevaluasi seluruh ternak, sedangkan untuk mengevaluasi pejantan, evaluasi harus diperpanjang sampai tiga catatan Test Day pada laktasi dua.

In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number
and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named ‘Binasoybean-5’ for largescale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

The present experiment was carried out to evaluate eleven genotypes including named varieties of French marigold under Chhattisgarh plains agro-climatic conditions in randomized complete block design. The performance of genotypes was observed with regard to vegetative growth, flowering and yield attributes. Genotypes IIHR MO-4, CGFM-5 and CGFM-3 performed better with respect to vegetative growth parameters. Genotype IIHR MO-4 was found to be earliest in bud appearance, flower bud opening and days for 50% flower bud opening. Genotype IIHR MO-2 recorded maximum flower diameter whereas, longest flowering duration was observed in Pusa Deep. Genotype CGFM-1 recorded highest number of flowers and flower yield per plant as well as per hectare.

Background: Soybean is an important source of food, protein and oil and hence more research is essential to increase its yield under different agro-ecological conditions, including stress. In this regard, four popular soybean varieties viz. Shohag, BDS-4, BAU-S/64 and BARI Soybean-5 were irradiated using Co 60 gamma rays to create genetic variation for earliness, higher seed yield and other desirable agronomic traits. Methods: The experiments were conducted at Bangladesh Institute of Nuclear Agriculture (BINA) Headquarters farm, Mymensingh during 2006-2009 and 28 elite mutant lines were selected for evaluation. The mutant line, SBM-22 derived from mother variety BARI Soybean-5 irradiated with 300Gy of gamma rays was found to be superior compared to other mutants. Considering the superior performance of mutant SBM-22 including 28 mutants and mother check variety BARI Soybean-5, were evaluated through different trials. The evaluation trials were conducted at different agro-ecological zones of the country during Rabi season (January to April) of 2010-2018. Result: Significant variations were observed both in individual location and over locations for all traits. Reactions to major diseases and insect-pests infestation were also studied. Due to better performance of the mutant SBM-22, Bangladesh Institute of Nuclear Agriculture (BINA) applied to the National Seed Board (NSB) of Bangladesh for registration as an important soybean variety "Binasoybean-6". Consequently, the NSB of Bangladesh registered SBM-22 as an improved soybean variety in 2019 as Binasoybean-6 for commercial cultivation.

To study some mitotic and meiotic parameters and irregularities of gamma ray irradiated (with two doses 4 and 8K r.) parents (M0), plants (M1) and their control of four onion cultivars (Giza 6, Giza 20 Shandawel 1 and Beheiri red), acetocarmin-squashed preparations were made and chromosome behavior of the PMCs (pollen mother cells) were also examined. The almost all investigated mitotic and meiotic cells in the present material showed a diploid number of 2n=16 chromosomes and the absence of cells with ploidy formula. The mitotic index of M0 control plants of Beheiri variety (23.15) was the highest than those of the other three varieties. In M0 irradiated plants of Giza 6 and Giza 20 varieties, the values of mitotic index were insignificantly different from that of the control plants. In contrast, the mitotic indexes in M0 irradiated plants of shandaweel 1 was considerably high than that of the control. The mitotic indexes of M1 plants (with 4Kr dose) were lower than those of 8 Kr in both Giza 6 and shandaweel 1 varieties. The M0 irradiated plants of Beheiri variety couldn't survive to the next M1 generation. Hence their mitotic indexes of M1 plants and subsequently their M1 control plants were not found. In general, the MI values of the M1 irradiated plants (particularly with 8Kr), were high than those of the control. The mitotic irregularity percentages of M0 irradiated plants were considerably high than those of M1 plants. The structural aberration (breaks, fragments, stickiness and Bridges) and micronuclei were the commonly observed aberrations in the mitotic cells. The M0 irradiated plants have a higher chiasma frequency than those of control in all varieties and treatments. In general the highest frequency of chiasma was recorded in irradiated plants (12Kr) of Beherie and Shandaweel 1 varieties. The appearance of univalent and multivalent was higher in irradiated plants than those of control. In the same manner, the highest percentage of irregular synapses (Uni-and multivalent) were higher in M0 irradiated plants than those of control. The Mo irradiated plants with 12 kr in Giza 6 variety exhibited the highest percentage of the structural aberrations. The control plants of all varieties showed the lowest values of structural aberrations in comparison with those of irradiated plants.

The objective of this study was to select cowpea [Vigna unguiculata (L.) Walp.] varieties that meet farmers' needs in Namibia, from a set of newly developed and elite cowpea varieties developed through gamma irradiation. Thirty four candidate mutant cowpea varieties derived from three local varieties, (Shindimba, Bira and Nakare), were evaluated for nine agronomic traits. The new genotypes descended from Bira were favourably selected by all participants for their best plant cover. The genotype L1P12 (Bi450) was preferred by 81 percent percent of farmers for its higher pod setting ability. The genotype R4P5 (Nk150) with longer pod size and R3P1 (Bi600) with early maturity were ideal candidates preferred by nearly all farmers. The present study has identified farmers' most-preferred cowpea varieties selected for their best agronomic performances and drought tolerance. These selected cowpea genotype lines will further be subjected to distinct, uniformity and stability trials for varietal registration and release.

ABSTRACT
Seeds of two varieties of cluster bean viz., Pusa navbahar and VRS-Culture were treated with of gamma-rays (80, 100 and 120 kR) and EMS (0.2, 0.3 and 0.4 %). The effect of mutagenic treatments on the character association was studied in M2 generation. Association study indicated that the relationship between traits was enhanced in few instances. In most cases, however, no significant change was observed and in few instances a definite decrease of association was found. This revealed that apart from generating variability, mutagenic treatments could alter the mode of association between any two characters and selection for improved plant architecture resulting from mutagen treated population could be possible.

Rice is a main source of food to millions of people across the world, and hence increase in its production/yield is vital to feed the rapidly growing population. However, the yield of rice is decreased to a large extent due to the adverse effects of several kinds of abiotic stresses such as drought, salinity, heat stresses, etc. Different traditional and modern breeding approaches have been used to mitigate the damaging effects of different abiotic stresses on the rice production. Traditional breeding strategies such as hybridisation and selection have resulted in the development of few stress-tolerant varieties, but such strategies are laborious and time-consuming. The modern biotechnological approaches such as mutagenesis, transgenics and genomics have been effective in the identification, cloning and characterisation of genes that govern tolerance to different abiotic stresses. Insertion of such genes into the rice plants have decreased the yield loss caused by various abiotic stresses. Modern biotechnological tools have brought landmark achievements by developing varieties with enhanced tolerance to various abiotic stresses. The role of mutagenesis, genomics and transgenic approaches in the creation of rice varieties with improved yield under different abiotic stress has been reviewed in this chapter.

This study was carried out to investigate the effect of different UV exposure time on the germination and early seedling growth of cowpea in order to ascertain the exposure time that affects these developmental stages of plant. The study was laid out in a randomized complete block design of six exposure times including control as treatments with five replicates. Growth parameters of cowpea such as plant height stem girth and number of leaves was determined daily after germination has taken place. All the cowpea seeds in all the treatments exhibited 100% germination at the end of the 9 th day. It was observed that the UV irradiation never had any significant negative effect on any of the growth parameters compared with control. This could be due to the short period of exposure or the resistance of the cowpea plant to UV irradiation.

Urginea indica Kunth commonly called as Jangli Pyaz or jangli dungli is a medicinal plant having very high therapeutic value. Due to over exploitation, it has become vulnerable in some places. So, development of genetically advanced varieties of this plant is needed so that we can avail the benefits of this plant for a longer period of time, with great ease to mitigate several human ailments. To develop such variations in the plants through mutation breeding, screening of the plant is the most important aspect. Therefore, in this research sensitivity of Urginea indica Kunth to Ethyl Methane Sulphonate was assessed through the measurement of the mutagenic effects on pollen grains. Dose dependent decrease in the pollen fertility was observed. In addition, variation in the shape and size of the pollen grains were also observed after treatment with different concentrations. Thus, Urginea indica Kunth was found to be sensitive to Ethyl Methane Sulphonate. Richa Sinha"Mutagenic effec...

The present investigation was designed to improve the genetic constitution of mungbean through gamma radiation induced mutation breeding approach to identify some high yielding mutant genotypes having extra short maturity duration. Three mungbean germplasms lines were exposed to gamma irradiation with three different doses and desirable mutants were selected from M 2 through M 5 generations. A total number of twenty mutant individuals from M 5 generation were identified as promising mutants having early maturity duration (<55 days) with high yield (>25 g seed yield plant-1). Among them, six were found to be extra ordinary mutants with extra early maturity dutation of <53 days with > 30g seed yield plant-1. Such mutants were not only high yielding extra early maturing type than their parents but also had synchrony in pod maturity, nonshattering pod and top fruitbearing habit. The identified mutants may be directly released as cultivars after their multilocation trials and can also be used as donor for improvement of mungbean with respect to earliness and yield.

Effect of 250Gy, 300Gy, 350Gy and 400Gy gamma rays on Badsabhog, popular non- basmati aromatic landraces of West Bengal was studied in M1 generation under field condition. In general, plant height, number of total tillers, effective tillers plant- 1 , panicle exertion, spikelet number panicle-1 , filled grains panicles-1 , productive tiller hill-1 , spikelet fertility (%), and grain yield plant-1 decreased with increase in dose at variable rate due to negative effect of mutation. Total tiller hill-1 , Primary branch panicle-1 and Secondary branches panicle-1 were increased in all the irradiated population over control, which might be due to stimulatory effect of mutagen. The results indicated the differential sensitivity of the genotypes and characters to radiation treatment. The overall results indicated that spikelet fertility percentage (%) was more sensitive to gamma irradiation as compared to other yield attributing characters in non-basmati aromatic rice.

Pakistan is well known for its basmati rice with long grain and aroma, as well as for non-basmati indica varieties; however average yield is lower as compared with other countries. Besides, cultural practices, the main reason for low productivity in Pakistan is that, local varieties are susceptible to different biotic and abiotic factors like insect pests, diseases, drought, and salinity. Different approaches have been undertaken in Pakistan to tackle these problems through traditional breeding of selection and crossing, mutation breeding, somaclonal variation as well as plant transformation studies in recent past. For variety development, the most successful examples arose from traditional breeding that produced famous basmati varieties like Basmati 370, Basmati 385 and Super basmati, and non-basmati varieties such as IRRI-6, DR-82, DR-83, DR-92, Swat-I and Swat-II, which earn a significant share of foreign exchange every year. Six varieties have also been developed through mutatio...

Mungbean is one of the most important pulse crops due to its nutritive value and maintaining soil fertility through biological nitrogen fixation. Genetic variability is one of the pre-requisite for crop improvement. The present investigation was aimed at to enhance the genetic variability for three quantitative traits viz. pod length, number of seeds per pod and 100-seed weight in M2 and M3 generations of mungbean following mutagenesis with ethylmethane sulphonate (EMS), hydrazine hydrate (HZ) and sodium azide (SA). Mean pod length did not differ significantly in most of the mutagenic treatments in M2. However, significant improvement for the trait was exhibited with lower and moderate concentrations in M3 generation. The mean number of seeds per pod and 100-seed weight increased with lower and moderate concentrations of the mutagens in M2, whereas M3 generation showed a complete positive trend of shift. Long pod and bold seeded mutants may be exploited to increase the number of see...

Once a person decides to proceed with genetic testing, a health care provider can arrange testing. Genetic testing is often done as part of a genetic consultation. Genetic tests are performed on a sample of blood, hair, skin, amniotic fluid (the fluid that surrounds a fetus during pregnancy), or other tissue. For example, a procedure called a buccal smear uses a small brush or cotton swab to collect a sample of cells from the inside surface of the cheek. The sample is sent to a laboratory where technicians look for specific changes in chromosomes, DNA, or proteins, depending on the suspected disorder. The laboratory reports the test results in writing to a person's doctor or genetic counselor, or directly to the patient if requested. Newborn screening tests are done on a small blood sample, which is taken by pricking the baby's heel. Unlike other types of genetic testing, a parent will usually only receive the result if it is positive. If the test result is positive, additional testing is needed to determine whether the baby has a genetic disorder.

Pakistan is well known for its basmati rice with long grain and aroma, as well as for non-basmati indica varieties; however average yield is lower as compared with other countries. Besides, cultural practices, the main reason for low productivity in Pakistan is that, local varieties are susceptible to different biotic and abiotic factors like insect pests, diseases, drought, and salinity. Different approaches have been undertaken in Pakistan to tackle these problems through traditional breeding of selection and crossing, mutation breeding, somaclonal variation as well as plant transformation studies in recent past. For variety development, the most successful examples arose from traditional breeding that produced famous basmati varieties like Basmati 370, Basmati 385 and Super basmati, and non-basmati varieties such as IRRI-6, DR-82, DR-83, DR-92, Swat-I and Swat-II, which earn a significant share of foreign exchange every year. Six varieties have also been developed through mutatio...