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An investigation was taken up to study the nutritional value, extent of genetic variability and genetic diversity in advance breeding lines and chickpea varieties grown in Andhra Pradesh, India. Protein and micronutrient content (iron, zinc, copper and manganese) varied significantly among 54 genotypes. Protein content ranged from 9.5% to 24.9% while micro nutrients varied from 2.6 mg/100 g to 14.6 mg/100 g for iron, 3.5 mg/100 g to 7.7 mg/100 g for zinc, 0.5 mg/100 g to 3.2 mg/100 g for copper and 1.6 mg/100 g to 3.4 mg/100 g for manganese. Moderate to high genotypic variability for protein and micro nutrient content with high heritability and genetic advance indicated the scope for enhancement of traits through selection. Genetic diversity studies revealed five different clusters and that high protein lines are grouped in cluster I and lines with higher concentration of micro nutrients are grouped in clusters IV and V. Systematic hybridization between promising lines for protein and micronutrients chosen from these clusters is suggested to study their combining ability and subsequent use in breeding programmes intended to breed for superior chickpea cultivars. [ABSTRACT FROM AUTHOR]

Background: Fusarium oxysporum f.sp. ciceris (Foc) is one of the most important pathogen, causing wilt of chickpea. It is soil and seed borne pathogen. A serious threat in Foc is the evolution of new races, which reduces exploitation of wilt resistance in the crop in a particular area. Eight races (race 0, 1A, 1B/C, 2, 3, 4, 5 and 6) were reported in the world and among them four races (race 1, 2, 3, 4) were from India. Race 1 was reported from Andhra Pradesh. It is very important to monitor the variation regularly in new isolates collected from different varieties or genotypes and different geographical regions to identify the racial pattern. Development of SCAR markers for identification of Foc isolates is also important as they are highly reliable. Methods: Twenty isolates of Fusarium oxysporum f.sp. ciceris were obtained from wilt infected plants of chickpea covering different places of Andhra Pradesh including two isolates from Telangana and confirmed the pathogen based on pathogenicity test. They were tested on host differentials of chickpea for races identification. Among these twenty isolates five most virulent isolates (Foc-6, Foc-10, Foc-12, Foc-17 and Foc-24) were selected for RAPD based on pathogenicity test and SCAR marker was developed based on DNA banding pattern during RAPD for one isolate. Result: Based on the disease reaction on differentials, concluded that 17 of them out of 20 were matched with race-1 reaction. Two isolates were matched with race-6 reaction and one is not matched with none of the races. An amplified product of polymorphic band of approximately 700 bp in the isolate Foc-12, obtained during RAPD analysis was selected for SCAR marker development and two SCAR markers were developed and validated. Identification of races mainly helps in development of resistant cultivars to specific races and might be contributed to development of integrated disease management practices for Fusarium wilt. [ABSTRACT FROM AUTHOR]

Sclerotium rolfsii is a soil borne fast spreading fungal pathogen that causes collar rot in chickpea. The variability among the pathogen isolates have made difficult to design efficient management practices and necessitates for a comprehensive study to know its diversity. The present study was planned to study the genetic diversity among the isolates of S. rolfsii collected from chickpea growing regions of Kurnool and Ananthapur districts of Andhra Pradesh at morphological and molecular level. The morphological characterization of isolates on PDA indicated that the isolates, CSR 14, CSR 18 and CSR 20, were fast growing and the overall growth i.e., sclerotia formation in terms of number, size and days to formation, was also faster. These isolates took only 4 days for production of sclerotial bodies. A total of 254 reproducible and scorable polymorphic bands ranging from 200 to 2000 bp were observed with twenty nine RAPD primers. The RAPD banding pattern reflected the presence of greater variability among the isolates and grouped the isolates into two clusters. The isolates, CSR 18 and 20, formed the cluster II revealing their distantness from other isolates at molecular level. The isolate, CSR 14, formed a separate sub cluster in the cluster I indicating its distant association with other isolates of this cluster. [ABSTRACT FROM AUTHOR]

Thirty two isolates of Fusarium oxysporum f.sp. ciceris (Foc) were collected from six districts of Andhra Pradesh (A.P) and three districts of Telangana. Based on wilting % in pathogenicity test, the isolates were grouped into three categories. All the isolates differed in cultural characters like mycelium colour, margin, texture, pigmentation and morphological characters like macro conidia, micro conidia length, width and chlamydospores diameter. There was no correlation between cultural and morphological characters of Foc isolates except three isolates (Foc-6, Foc-12 and Foc-17). These three isolates have white mycelium, cream colour pigmentation, slow radial growth and highly pathogenic (100% wilt incidence) in nature. Sporulation ability and radial growth of all isolates were also measured. All the isolates exhibited genetic variation in RAPD banding pattern and three major clusters (I, II and III) were found in the dendrogram. Maximum genetic similarity of 80.3% was observed between Foc-27 and Foc-28 isolates. [ABSTRACT FROM AUTHOR]

Chickpea, blackgram and greengram are important rabi pulse crops grown in Andhra Pradesh. Adoption gaps were identified in these crops indicating the need for the demonstration of the improved crop management practices. In chickpea the variety NBeG47, blackgram TBG 104, greengram variety WGG 42 were introduced in farmers fields in rabi season. Along with the varietal introduction the whole package of improved management practices were demonstrated. A total of 50 FLDs each in chickpea, blackgram and greengram were organized for two consecutive years 2016-17 and 2017-18 in Krishna district, Andhra Pradesh. Highest yield of 27.50 q/ha was recorded with NBeG-47 in the demo fields with an average yield of 25.50 q/ha. In blackgram a highest yield of 17.25 q/ha was recorded in the demo with an average yield of 14.59 q/ha as againstcheck with an average yield of 11.50 q/ha. In greengram a highest yield of 16.50 q/ha was recorded in the demo fields with an average yield of 15.12 q/ha as against check with an average yield of 10.00 q/ha. Paired t test of the economics of demo and check showed significant positive difference between improved practice and farmers practice. [ABSTRACT FROM AUTHOR]

Studies on genetic divergence carried out at Regional Agricultural Research Station, Nandyal, of Scarce Rainfall zone of Andhra Pradesh classified 113 chickpea genotypes into eight clusters. Cluster I was the largest with 69 genotypes followed by cluster III with 21 genotypes. Maximum inter cluster distance was observed between VII and cluster VIII (22.00) followed by clusters VI and VII (20.02) whereas, days to 50 % flowering (41.25 %) followed by 100 seed weight (23.28 %), plant height (17.29 %) and number of pods (7.32 %) contributed maximum towards diversity. Based on inter cluster distances and Per se performance ICCV 13124, ICC 4918, ICC 4872 and ICCV 2969, ICCV 6306, ICCV 15697, ICCV 15333, ICCV 7272, ICCV 15518, ICCV 7308 and ICCV 4814 were identified for inclusion in hybridization programme for realizing desirable transgressive segregants. [ABSTRACT FROM AUTHOR]