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Biochemical defense response and genetic basis of resistance against Ascochyta blight (Ascochyta rabiei (Pass.) Labr.) in chickpea (Cicer arietinum L.)
(Punjab Agricultural University, 2024) Abassy, Omer; Dr Upasana Rani
Chickpea (Cicer arietinum L.), the second-largest global pulse crop, is under threat from highly variable nature of Ascochyta rabiei, causing widespread disease damage under favourable environmental conditions. This disease, Ascochyta blight is a major concern worldwide, with insufficient resistant sources and frequent breakdowns due to rapid pathogen evolution. This study evaluated 238 kabuli chickpea genotypes for resistance to Ascochyta blight (AB) over the growing seasons from 2019-2022 at Punjab Agricultural University under artificial epiphytotic conditions, identifying 18 resistant lines (GLK 10-40, GLK 20054, GLK 20055, FLIP 10-298C-IFC-S2, FLIP 10298C-IFC-S1, CS-3-E-24, FLIP 09 256C-55, FLIP 07-314C-57, FLIP 10-243C, FLIP 09-194C, FLIP 08-104C, FLIP 04-219C, ICCV 55233, ICCV 55215, ICCV 55135, ICCV 55108 and ICCV 155141) belonging to different genetic backgrounds with disease scores of 1.0 to 3.0, whereas seventy-three (73) lines demonstrated a moderate level of disease resistance with a disease rating of 3.1-5.0. The activities of defense-related enzymes (PAL, TAL, PPO, POD) associated with phenol metabolism along with lignin and total phenol content were compared among six kabuli chickpea lines, viz., five resistant (GLK 10-40, GLK 20055, FLIP-09-194C, FLIP-04-219C, ICCV 55215) and one susceptible (GLK 17301) treated lines that exhibited differential responses to Ascochyta blight at tested time intervals of 48, 96, 144 and 240 hr post-inoculation respectively. The perusal of data showed increased activity of all enzymes (PAL, TAL, PPO, POD) till 96 hr after inoculation, whereas the non-enzymatic contents such as lignin and total phenols showed the maximum enzyme activity till 144 hr after inoculation. However, enzyme and non-enzymatic activity remained almost constant with no significant difference in all control/untreated resistant and susceptible line(s) at different time intervals. For understanding the genetic basis of resistance, the F2 population comprising of 162 plants derived from the cross, GLK 24096 (resistant) and L 556 (susceptible) was assessed under artificially epiphytotic conditions against local isolate of Ascochyta rabiei. Of 162 plants evaluated, 39 plants were grouped in resistant (R ) category (disease score ≤ 5.0 ) and 123 were classified as susceptible (S) with score of five and above. Consequently, the F2 plants exhibited a segregation ratio of 1R:3S, suggesting that a monogenic recessive gene governed resistance to Ascochyta blight. Of thirty four SSR markers associated with Quantitative Trait Loci (QTLs)/genes were used for confirmation of resistance in identified eighteen resistant and six susceptible lines, only 19 SSR markers depicted polymorphism. Notably, SSR markers, STMS11, TA194, TS12, TA146, and TA2 exhibiting significant polymorphism, indicated tight linkage to Ascochyta blight resistance. Phylogenetic analysis showcased distinct clustering based on resistance, offering insights into the genetic basis of resistance. These findings informed about targeted resistance breeding and sustainable disease management with defence-related enzymes/identified markers holding promise for developing superior, resistant and resilient chickpea varieties contributing to crop sustainability and productivity.
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CRISPR/Cas9-mediated pectate lyase gene editing for enhanced shelf life of tomato (Solanum lycopersicum L.)
(Punjab Agricultural University, 2024) Sumedha; Dr Prashant Mohanpuria
Tomato is one of the most consumed vegetable crops worldwide. Tomato fruits are having an inherently short shelf life which is directly related to fruit softening, caused by cell wall modifying enzymes. Among which pectate lyase (PL) controls fruit softening and thus PL gene was targeted using CRISPR/Cas9 to enhance shelf life of tomato variety Punjab Ratta. In silico study of PL genes from Solanaceous crops including tomato was attempted and three sgRNAs were designed from exon-2 of PL gene. The CRISPR/Cas9 constructs containing sgRNA-1 and 2 were used for transformation of tomato. A new in planta transformation protocol was developed with 10.49 % overall transformation efficiency. Floral buds of 3-8 days of developmental stages were used for dipping in Agro suspension which resulted in setting of 150 fruits. The extracted T0 seeds were selected on kanamycin. A total of 3240 T1 generation plants were regenerated from transgenic tomato fruits (T0), out of which 1620 were found kanamycin resistant which were used for DNA isolation and PCR confirmation of T-DNA integration. The 425 bp PL gene target region from 170 transgenic tomato T1 plants was PCR amplified. Upon sequencing eight T1 tomato transgenic plants were found with PL gene edits containing T insertion, T insertions as well as T substitutions, GC substitution by CG as well as TT insertion downstream to PAM site. PL gene expression and pectin content were decreased in fruits of mutated tomato plants but morphological and biochemical characteristics were more or less similar.
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Genome wide association studies for sorghum shoot fly and red leaf spot resistance
(Punjab Agricultural University, 2024) Jasneet Kaur; Dr. R.S. Sohu
The present study was conducted for the assessment of shoot fly and red leaf spot resistance and discovery of markers and candidate genes associated with target traits in Sorghum bicolor across years and locations. A diversity set of 121 germplasm lines, acquired from ICRISAT and IIMR, was evaluated under two environments (two locations – Ludhiana (2020-21 and 2021-22) and Faridkot (2021-22)) for shoot fly whereas at Ludhiana for two years kharif 2020-21 and 2021-22 for red leaf spot disease. The germplasm lines were evaluated for nine morphological traits for shoot fly representing- per cent dead heart formation (DH), glossiness(GL), leaf sheath pigmentation (LSP), plants infested with eggs (PWE), number of eggs per plant (PPE), seedling vigour (SV), seedling height (SDH), plant height (PH) and number of tillers (TL). Significant genetic and genotype x environment interaction variance was observed for all test traits. Ten genotypes viz., IC 288122, IS 7657, IS 7663, IS 7745, IS 8155, IS 8282, IS 8256, IS 8348, IS 8230 and SSV 17 were found resistant and gave stable performance across all environments. Resistant genotype IS 8348 was selected for generation of bi-parental cross with susceptible genotype IS 7017. Similarly, disease score and area under disease progressive curve was used for assessment of red leaf spot disease. Significant genetic variance and genotype x environment interaction variance was observed for disease score under both the environments. Four lines viz., IS 7017, IS 8015, IS 8256 and SCL 4 were free from infection, indicating resistance to red leaf spot. Best linear unbiased predictors values (BLUP) of traits were used for genome-wide association study (GWAS) using 42678 SNPs. Linkage disequilibrium decay in population was estimated to be ~50kb. A large number of significant marker-trait associations were identified for all test traits. The genomic regions identified on chromosomes 1, 2, 4, 7 and 10 were previously reported to be associated with shoot fly resistance for trait DH and GL. Annotations helped to predict candidate genes in the genomic regions associated with the significant SNPs. Important candidate genes involved were receptor kinases (LRR, serine/threonine protein kinases, hydrolases and transferases), stress signalling pathways (ethylene, abscisic acid and jasmonic) for shoot fly and (RLP, WRKY, F-box protein, CDP, zinc finger and putative disease resistance protein) for red leaf spot disease. Associative SNPs were converted into KASP markers and S1_15319241 KASP marker associated with DH was validated in the F2 population of cross IS 8348 x IS 7017.
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Status of trace elements and electrolytes in pregnancy induced hypertension and its effect on neonatal health
(Punjab Agricultural University, 2023) Himlesh; Grover, Kiran
The present study was conducted to assess the prevalence and determinants of pregnancy-induced hypertension (PIH) along with the effect of maternal status of trace elements and electrolytes on neonatal health in Punjab. The prevalence of pregnancy induced hypertension was found to be 8.1 percent which was further observed as gestational hypertension (90%), preeclampsia (7.5%) and eclampsia (2.5%). The history of chronic hypertension (r=0.86), diabetes Mellitus (r=0.38), hypothyroidism (r=0.37), Poly Cystic Ovarian Disease (r=0.22) and family history of hypertension (r=0.22) was observed as the significant (p<0.05) determinants of pregnancy induced hypertension. The comparative assessment of trace elements and electrolytes between normotensive (n=30) and hypertensive antenatal subjects (n=30) conducted in Government Rajindra Hospital, Patiala revealed a significantly (p<0.05) higher mean Systolic and Diastolic Blood Pressure of hypertensive subjects. A significant difference in daily food intake and serum concentration of trace elements (calcium, magnesium, iron, selenium, copper and zinc) and electrolytes (sodium, potassium and chloride) was also observed. The effectiveness of diet counseling was evaluated by selecting two groups of pregnancy induced hypertensive subjects i.e. Experimental (with diet counseling) and Control (without diet counseling). The diet counseling based on Dietary Approaches to Stop Hypertension (DASH) was provided to experimental group for 3 months at a regular interval of 15 days. The findings reported significantly lower Systolic ( 143.8±20.6 vs 150.7±11.4 mmHg) and Diastolic (93.5±3.9 vs 96.8±5.96 mmHg) Blood Pressure in experimental group. The counseling resulted in significantly (p<0.05) higher mean intake of fruits, vegetables, milk and milk products in experimental group. Further, the trace elements levels were also observed to be significantly (p<0.05) higher in experimental group with better neonatal outcome. Hence, nutrition and diet counseling should be provided to all the women of reproductive age group to manage the pregnancy related complications for better health of neonates.
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Quantitative and qualitative assessment of social support and digital addiction as correlates of purpose in life among adolescents
(Punjab Agricultural University, 2024) Vitasta; Kang, Tejpreet Kaur
The purpose of the present study was to ascertain the relationship of social support and digital addiction with purpose in life among adolescents. It also aimed to conduct case studies of identified typical adolescents with clarity or confusion of purpose in life. The study was conducted in two phases: phase I (quantitative phase) was based upon a sample of 500 adolescents in the age group of 16-18 years and was equally distributed across gender and locale. In phase II, 4 typical adolescents with clarity (2) and confusion (2) of purpose in life were selected to conduct case studies. A self-structured demographic information sheet, Child and Adolescent Social Support Scale (Malecki and Demaray 2002), Internet Addiction Test (Young 1995) and The Youth Purpose in Life Scale (Chaddha and Bano 2018) were used to collect the relevant data. Results revealed that girls perceived more social support and had higher purpose in life as compared to boys. Further, adolescent boys displayed higher digital addiction as compared to girls. Locale differences showed that urban adolescents significantly had better social support and scored more in commitment towards goals, society-oriented goals and overall purpose in life as compared to rural adolescents. Significant locale differences were observed in digital addiction where urban adolescents displayed higher digital addiction as compared to rural adolescents. Correlational analysis revealed that purpose in life was significantly and positively correlated with social support. A statistically significant negative correlation existed between purpose in life and digital addiction.
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Development of monoecious lines in muskmelon (Cucumis melo L.) through marker assisted selection
(Punjab Agricultural University, 2024) Nidhi; Sharma, Sat Pal
In heterosis breeding, monoecious sex expression offers significant advantages over andromonoecy in muskmelon, as it eliminates emasculation and produces fruits with desirable traits, such as earliness, high TSS, thick flesh, small scar size, and large fruit size. Thus, development of stable monoecious lines possessing desirable horticultural traits is critical for hybrid breeding in this crop. This investigation was aimed to identify molecular markers linked to monoecious trait and to transfer this trait to a popular melon cultivar through marker assisted selection. For this purpose, stability of monoecism was assessed under varying environments and identified 18 stable monoecious using the andromonoecious index. A set of identified lines was used to develop KASP markers for the sex-determining gene, CmACS-7, which revealed two mutations in exons 1 and 2, with one SNP at 170th, followed by insertion of ‘GA’ at 222nd nucleotide position. Upon validation, KASP-CT-2 accurately separated homozygous andromonoecious and monoecious parents and was also successfully validated on F2 population segregating for monoecious trait. Subsequently, marker-assisted backcross breeding was carried out to transfer the dominant gene 'A' controlling the monoecious trait into the Punjab Sunheri, a popular muskmelon cultivar. Heterozygous plants in BC1F1 and BC2F1 and homozygous plants in BC2F2 with high recurrent parent genome recovery and monoecious trait were advanced using the cleaved amplified polymorphic sequence (CAPS) marker. In the BC2F2 population, homozygous monoecious plants were identified using the CAPS marker. These plants were self pollinated to generate a BC2F3 progenies, of which 11 out of 13 lines had phenotypic similarities with the recurrent parents. These 11 lines were self pollinated to generate 34 BC2F4 progenies. Eight BC2F4 lines, viz. Mono-6R2, Mono-IOB1, Mono-2OB3, Mono-7R3, Mono-2OV2, Mono-1OB2 were selected based on TSS, TSS/TA ratio, β-carotene, low titratable acidity, pH, flesh thickness, fruit shape index, and yield. The information and developed associated molecular marker will be useful in developing new stable monoecious lines. Furthermore, the generated monoecious lines can potentially be utilized as a female parent for F1 hybrid development in muskmelon.
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Effect of biochar and bacterial endophytes on salinity tolerance in oats (Avena sativa L.)
(Punjab Agricultural University, 2023) Arshdeep Kaur; Gupta, Namarta
The present investigation was carried out to study the effect of biochar and plant growth-promoting bacterial endophytes for salt tolerance in oats (Avena sativa L.). Forty four morphologically distinct salinity-tolerant endophytic bacteria were isolated from the leaf, stem and root samples of oats on nutrient agar with 2.5% NaCl and screened for the production of ammonia, auxins, siderophore and HCN; solubilization of Ca3(PO4)2, ZnO, Zn3(PO4) and ZnCO3 and salt tolerance up to 12% NaCl. Bacterial isolates showing high salt-tolerance and plant growth-promoting traits were selected and tested for growth promotion of oats on 1% H2O agar plates. Three potential isolates were identified based on polyphasic approach as Enterobacter quasiroggenkampii O1SE4, Bacillus inaquosorum O3SE2 and Bacillus safensis O4SE1. The SEM analysis showed the colonization of the plant tissues by all the three bacterial strains. Total 25 genotypes were screened for germination parameters viz. percent germination, shoot length, root length, seedling length, fresh weight, dry weight, vigour index I and II, proline, SOD, POD and CAT under salt stress conditions and were grouped into highly salt tolerant, moderately salt tolerant, moderatly salt sensitive and highly salt sensitive. Among seed treatments, the combination of biochar (2%) and Bacillus safensis maximally improved the above parameters as compared to the other treatments of Enterobacter quasiroggenkampii, Bacillus inaquosorum and biochar (1%). The evaluation of biochar and bacterial strains was done in two salt tolerant and two salt sensitive genotypes grown in the pots. The highest plant height, SLW, NAR were observed with the bacterial treatment (Bacillus safensis) + biochar (2%). Among biochemical parameters chlorophyll, carotenoid, total soluble sugar, starch, total soluble protein and free amino acids along with activities of antioxidant enzymes SOD, POD and CAT were enhanced by the application of Bacillus safensis and biochar (2%). Na+/K+/Ca2+/Mg2+ homeostasis was maintained by biochar and bacteria application. In conclusion, it is stated that the combined use of biochar and halotolerant endophytic bacteria can be used for improving the crop growth under salt stress in oats.
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Optimizing sub-surface drip fertigation system for better productivity and resource use efficiency of cotton-wheat cropping system
(Punjab Agricultural University, 2024) Vaddula Yamini; Kulvir Singh
Sustainability concerns have loomed over cotton-wheat cropping system (CWCS) as conventional irrigation and fertilization methods have been resulting in huge wastage of water besides leaching of nutrients. This has stimulated an interest in sub-surface drip fertigation (SSDF), which could serve as transformative solution offering precise nutrient and water delivery to the crop. Therefore, a two-year field study was conducted during 2021-22 and 2022-23 at PAU, Regional Research Station, Faridkot to optimize lateral depth, emitter spacing and fertigation scheduling for sub-surface drip fertigated cotton-wheat cropping system. Experiment was laid out in a Split-Plot Design with a combination of lateral depths (25 ± 2.5 cm and 30 ± 2.5 cm) and emitter spacings (30 and 40 cm) in main plots and fertigation schedules [100% N (112.5 kg ha-1) and 125% N in 10 and 14 equal splits (cotton); 80 and 100% NP (100:50 kg NP ha-1) in 08 & 10 equal splits (wheat)] in sub plots. Two additional control treatments i.e., (surface flood irrigation with 100% RDF through manual broadcasting of fertilizers and SSDF at 20 ± 2.5 cm depth, 20 cm emitter spacing, and 100% RD N for cotton, and 80% RD NP for wheat) were also studied. Placing sub-surface drip laterals at 25 ± 2.5 cm and emitter spacing of 30 cm increased seed cotton yield by 15.4 and 8.7 per cent, and wheat grain yield by 7.7 and 3.7 per cent, respectively as compared with the deeper lateral placement (30 ± 2.5 cm) and wider emitter spacing (40 cm). Among fertigation levels, application of 125% N in 14 equal splits recorded 18.6 per cent higher SCY (3432.2 kg ha-1) over 100% N delivered in 10 equal splits (2895.1 kg ha-1). The productivity of CWCS under SSDF was improved by 18.6 per cent, when cotton and wheat were fertigated with 125% N in 14 equal splits and 100% NP in 10 equal splits, respectively in comparison to 100% N applied in 10 equal splits (cotton) and 80% NP application in 08 equal splits (wheat). Sub-surface drip fertigation with 125% N in 14 equal splits improved net returns by 49.7-54.2 per cent, besides saving 57.4-58.8 per cent of irrigation water relative to surface flood irrigation in cotton. Whereas, fertigation with 100% NP in 10 equal splits improved net returns by 21.6-16.2 per cent, additionally saving irrigation water by 45.9-47.7 per cent as compared with surface flood irrigation in wheat. Furthermore, lateral placement (25 ± 2.5 cm), emitter spacing (30 cm), and higher fertigation level [125% N in 14 equal splits (cotton) and (100% NP in 10 equal splits (wheat)] improved crop, irrigation and total water productivity indices by 1.3, 3.1, and 2.1 folds, respectively as compared with surface flood, accentuating the inefficient use of applied water by surface flood method of irrigation. These findings elucidated that SSDF with lateral placement of 25 ± 2.5 cm, emitter spacing of 30 cm, and N fertigation of 125% N (140 kg N ha-1) in 14 equal splits (cotton); 100% NP (125: 62.5 kg NP ha-1) in 10 equal splits (wheat) could be a novel and sustainable water-savvy concept in improving the growth and productivity of cotton-wheat cropping system in North-Western India.
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Status and Performance of Farmer Producer Organisations (FPOs) in Selected States of India
(Punjab Agricultural University, 2024) Sandhu, Karanvir Singh; Pankaj Kumar
The present study was undertaken with the objectives to study the status, performance, linkages and problems of Famer Producer Organisations (FPOs) in Punjab, Haryana and Maharashtra. Fifteen FPOs were selected for the study, five from Punjab, Haryana and ten from Maharashtra. Five management committee members from each FPO were selected, making a total of 75. 300 members farmers from the FPOs were selected using probability proportional to number of member farmers in each FPO. Data were collected by personal interview method. It was observed that majority of the FPOs originated post-2015 with primary engagement in cereals and vegetables crops. Majority had warehouses, collection centres and input shops. Farmer‟s reliance on experts from FPOs was highest amongst all the extension contacts in Maharashtra whereas, pesticide dealers were most contacted in Punjab and Haryana. Exposure to digital platforms than traditional media with YouTube emerged as the most dominant media with first rank in both the regions. Most of farmers across both regions had medium economic motivation and risk-bearing capacities. Consumption of quality food, balanced diet, access to educational information and adult education witnessed an increase in Maharashtra. Enhanced social empowerment was evident across both regions with Maharashtra depicted a higher increase. About half of farmers in Punjab and Haryana were satisfied, whereas about 40 per cent of farmers in Maharashtra were very satisfied with FPOs. Majority of farmers in Punjab and Haryana relied on Co-operative Banks/Societies and informal channels and about two-third farmers in Maharashtra were also dependent on Co-operative Banks/Societies for credit requirements. A stronger financial support was exhibited by FPOs in Maharashtra for the members. While private dealers remained central for all agri-input requirements, co-operative agencies held significant position particularly for seeds, fertilizers and pesticides. FPOs in Maharashtra took a lead in training initiatives with government agencies playing a noticeable role in both regions for capacity building. Extent of linkage of member farmers with FPOs was high for immediate necessities like credit for inputs, fertilizers and pesticides in Punjab and Haryana. The private sector was found to be dominant in fulfilling the input requirements of FPOs in Punjab and Haryana, while Maharashtra had a diverse supply system for agri-inputs. Linkages for technical support in Punjab and Haryana primarily depended on government departments. FPOs in Punjab and Haryana were mainly dependent on member farmers for procurement, whereas Maharashtra demonstrated a comprehensive strategy. Lack of transport facilities (47.00%), crop insurance facilities (42.00%), processing facilities (42.00%), adequate knowledge about cultivation practices (40.00%) and credit facilities (39.33%) were the major problems of member farmers. Some of the major challenges of FPOs were huge capital requirement for starting FPO (80.00%), non-cooperative attitude of members (66.67%), ineffective linkages (66.67%), political affiliation of members (50.67%), price fluctuation of agricultural produce (41.33%) and lack of technical experts (45.33%).

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