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A field experiment was carried out to determine the genetic variability, heritability and Genetic advance present in twenty-two genotypes of garden pea during Rabi season 2021-22 at ICAR-Krishi Vigyan Kendra, Babbur farm, Hiriyur. The experiment was laid out in Randomized Complete Block Design with two replications. Observations were recorded on various yield and yield contributing characters. In general, the magnitude of the phenotypic coefficient of variation (PCV) was greater than that of the genotypic coefficient of variation (GCV) and the narrow difference between them indicates less environmental influence on the expression of the trait. High PCVand GCV (>20%) were recorded on plant height, number of branches per plant, pod thickness, number of pods per plant and non-reducing sugars which indicates the presence of high genetic variation and scope for effective improvement. All the characters studied in this experiment showed high heritability (>60%) in a broad sense coupled with high genetic advance as per cent over a mean (>20%) except for days to first flowering, days to 50 per cent flowering and days taken for first picking. This indicates the existence of additive gene action and the need for population improvement through selection. The genotypes that exhibit specific traits can be used in a hybridization programme

Gamma ray is an effective mutagen which creates useful variability for crop like cluster bean where the natural variation is very meagre and creation of variability by conventional methods is cumbersome. In the present study, cluster bean cv. Pusa Navbahar was treated with different level of gamma rays from 50 Gy to 600 Gy with 50Gy interval and obtained M2 population was subjected to variability estimation for yield and its attributing traits in augmented block design. The variance between the control and the mutants was found to be significant for plant height, number of pods per cluster, number of pods per plant, pod length, pod width, pulp to seed ratio. For these traits, PCV ranged from 14.28 per cent (pod width) to 31.99 per cent (pulp to seed ratio) whereas, GCV ranged from 10.10 per cent (pod width) to 24.16 per cent (pulp to seed ratio). The heritability in broad sense ranged from 50 per cent (pod width) to 79.99 per cent (Plant height). Genetic advance expressed as percentage over mean ranged from 2.06 per cent (pod width) to 222.44 per cent (plant height). The traits like plant height, pod length, pod width, pulp to seed ratio showed sufficient variability due to induced mutation. All these traits showed medium to high heritability and high genetic advance hence selection for these traits will be effective.

The present investigation is aimed towards breeding varieties of garden pea for early summer cultivation (March-May) that can tolerate temperatures up to 35 0C. High temperature tolerant accessions KTP-4, Arka Sampoorna, Oregon Sugar, Magadi local were crossed with Arka Ajit, Arka Pramodh, Arka Priya having superior pod quality, yield and followed by pedigree method of breeding, superior transgressive segregants from these crosses were advanced up to F 7 generation. In F 7, six selected advanced breeding lines were assessed for their performance in the field with checks during early summer for four years in succession. Results revealed significant differences between selected lines and checks wherein all the lines surpassed checks with yield ranging from 5.9-7.6 t/ ha and in checks it was only 2.6-3.1 t/ha. Among these six breeding lines, three lines were selected based on high yield (6.7-7.6 t/ha), pod quality characters and identified to be highly suitable for early summer cultivation.

Photosensitivity in pole types of vegetable dolichos is a major production constraint limiting its production to rabi. Presently, the pole type varieties are gaining popularity among farmers because of their higher yield levels. To accomplish the development of high yielding, pole type and photo-insensitive varieties, hybridization was done between (IC 556824-IPS-2 X Arka Swagath) and (IIHR 178 X Arka Swagath), wherein superior transgressive seggregants from both the crosses were selected and crossed with Arka Amogh. Followed by pedigree method of breeding, the lines were advanced upto F7 generation wherein six advanced breeding lines comprising of photo-insensitive trait, high yield and promising pod characters were selected and evaluated using pole type check varieties during both kharif and rabi for three years in succession from 2015-2017. All the advanced breeding lines had normal flowering in both the seasons as well as outperformed the checks with yield ranging from 37.2 to 41.1 t/ha during kharif and 37.9 to 41.4 t/ha in rabi, whereas in checks yield was comparatively lower ranging from 15.2 to 26.3 t/ha and 17.4 to 26.7 t/ha during kharif and rabi respectively.

Vegetable crops with great species diversity play an important role in human nutrition. India, with diverse agro-ecological regions, is the second largest producer of vegetables. Vegetable cultivation offers nutritional security, gainful employment and constant income to the farmers. However, vegetable crops face abiotic stresses like high temperature, excess moisture, deficit moisture and salinity stresses at critical growth stages. These abiotic stresses individually and or in combination affect vegetable crops adversely. The ill effects on physiology, phenology and growth subsequently influence the yield and quality of vegetable crops. Thorough understanding of the response of different vegetable crops and their cultivars aids in devising suitable management strategies to ease adverse effects of abiotic stresses. Efforts have been made by many researchers to devise crop management practices under such conditions. The management strategies like change in planting dates, production and planting of healthy seedlings, water-saving irrigation methods, mulching, advanced irrigation practices, use of microbes, grafting technique, choosing appropriate crops and tolerant cultivars in the areas frequently encountering abiotic stress are suggested in this chapter.

Mungbean yellow mosaic virus (MYMV) causes yield loss up to 80 % and is becoming problematic in French bean growing areas. Molecular marker linked selection to MYMV resistance is helpful in rapid identification of genotypes carrying resistant genes. Hence, the present study was undertaken to identify the RAPD marker associated with MYMV resistance in French bean (Phaseolus vulgaris L.). Bulk segregant analysis (BSA) was used to identify RAPD marker linked to MYMV resistance. More than 140 random decamers were surveyed for identification of polymorphic markers between the DNA bulks of resistant and susceptible F2 individuals and their contrasting parents. Ninety eight per cent of these primers amplified DNA in both parents and bulks. Twenty two primers produced specific bands for resistant parent which was absent in the susceptible parent. Out of 22 primers, four primers produced specific fragments viz., OPG 13458, OPX 5670, OPW 17380 and OPP 07730, respectively in resistant parent and bulk, which were absent in susceptible parent and bulk. Amplification of individual DNA samples of segregating F2 resistant individuals using putative marker, OPP 07730, a decamer revealed polymorphism in all four resistant and four susceptible F2 segregants, indicating that the marker OPP 07730 was associated with MYMV resistance in IC-525260, a resistant genotype.

Cluster bean is a highly self- pollinated vegetable with a very narrow genetic base. Hence, mutation breedingis a viable option for generating variation. In the present study, effect of mutagen was studied in Pusa Navbaharvariety of cluster bean using gamma rays from 50 Gy to 600 Gy. Preliminary evaluation at M1 generationfor germination and seedling growth parameters revealed at lower doses of 100 to 200 Gy germination andgrowth parameters showed improvement over control. Further pollens showed steady increase in sterility withincreasing dose and mutated lines showed less survivability compared to control. Thus, 100-200 Gy gammairradiation was found useful to improve the seed germination and seedling growth parameters in cluster bean.While evaluating M2 generation, total 9 types of mutants (dark green, branched, dwarf, white flower, sterile, longpod, short pod, curve pod, small leaf) were observed and the mutation frequency was high at higher doses,whereas both mutagenic effectiveness and efficiency showed decreasing trend with increasing dose. Highestmutation effectiveness was observed at 50-100 Gy. Mutation efficiency based on pollen sterility was maximumat 50 Gy and based on lethality, it was maximum at 150 Gy.

SummaryA major disease in garden pea (Pisum sativum var. hortense) is powdery mildew caused by Erysiphe pisi. Homozygous recessive alleles of the er1 and er2 genes, and the dominant allele of Er3 have been found to contribute to powdery mildew resistance in pea. Nine parental genotypes used for pea breeding in India were screened using 12 sequence characterised amplified region (SCAR) markers and five simple sequence repeat (SSR) markers. None of the SCAR markers could differentiate between the resistant or susceptible genotypes, although they amplified at the specific loci previously reported. The SSR marker A5 clearly distinguished the homozygous resistant and susceptible parents and three F2 progeny from crosses of ‘Arka Priya’ × 'IP-3’, ‘Arka Pramod’ × ‘IP-3’, and ‘Arka Ajit’ בAzad-Pea’. Chisquare analysis showed a 1:3 phenotypic segregation pattern and a genotypic ratio of 1:2:1 for the SSR marker A5. Since SSR A5 is a co-dominant marker, it distinguished the clear homozygous (Er1Er1/er1er1) and het...

Two resistant parents Arka Anoop and IC-525236 , three susceptible parents IIHRPB-1, IIHRPB-2 and IIHRPB-7 and six crosses IIHRPB-1×Arka Anoop, IIHRPB-2×Arka Anoop, IIHRPB-7×Arka Anoop, IIHRPB-1×IC-525236, IIHRPB-2×IC-525236 and IIHRPB-7×IC-525236 were screened for rust resistance under artificial epiphytotic conditions at Indian Institute of Horticultural Research, Bengaluru, during rabi, 2012. Studies were made on the resistant components viz., Stomata count both on upper and lower surface, Stomatal size (length and breadth), and stomatal pore size. Among the genotypes screened against rust under natural and artificial epiphytotic conditions, all the resistant parents and crosses did not show disease symptom and had less no. of stomata, small stomatal and narrow stomatal pore than all three susceptible parents which showed disease severity. The results indicated that the physiological basis of resistance, the structural features of stomata, like small stomatal pore size, narrow stoma and reduced number of stomata are highly related to impart rust resistance in french bean cultivars.

French bean ( Phaseolus vulgaris L.) 2n=14 is an important legume vegetable grown for its tender green pods which are rich in proteins, minerals and dietary fibre. Though it is a short duration crop, it is prone to several biotic and abiotic stresses. Among the biotic stresses, rust caused by Uromyces phaseoli (Reben Wint) has become epidemic in bean growing areas and the yield loss to the tune of 80% is reported. Rust fungi have wide variability in pathogenicity and also demonstrate frequent sexual recombination and more than 150 physiological races of the pathogen are reported. Hence, the induction of genetic resistance is always preferred because it is least expensive and has no adverse environmental effects. Inheritance of rust resistance was studied in F 2 generation by using molecular markers. Resistance was confirmed in parent genotype IC525236 by using SK 14. In IC525236 resistance to rust is controlled by single dominant gene.