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Author: Harleen Kaur × Start date: 1972 × Thesis Type: Ph.D ×
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    Assessment and management of climatic variability impact on evapotranspiration and water productivity of Maize (Zea mays L.) in Punjab
    (Punjab Agricultural University, Ludhiana, 2018) Harleen Kaur; Kingra, P.K.
    ABSTRACT The field experiment entitled, “Assessment and management of climatic variability impact on evapotranspiration and water productivity of maize (Zea mays L.) in Punjab” was carried out at the Research Farm of the Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana for two consecutive kharif seasons of 2016 and 2017. The field experiment comprising of 12 treatments was carried out in split plot design with 3 replications having three dates of sowing (D1-Third week of May, D2-Second week of June and D3- First week of July) in main plots and two irrigation levels i.e. irrigation at IW: CPE of 1.00 (I1) and 0.75 (I2) and two mulch levels viz. mulch @ 5 t ha-1 (M1) and no mulch (M2) in the sub-plots. The soil of the experimental site was loamy sand in texture with normal pH and electrical conductivity and low in organic carbon. PAR interception and relative humidity was highest in D2 as compared to D1 and D3 and among irrigation and mulch treatments in I2 and M1. The canopy temperature was highest in D3 as compared to D1 and D2 and among irrigation and mulch in I1 and M2 treatments at reproductive stage of crop. Higher plant height, dry matter and LAI was observed in the crop sown during second week of June and among irrigation and mulch treatments in I2 and M1. The total water use was more in D1 (540.5 and 477.5 mm) as compared to the D2 (493.3 and 399.0 mm) and D3 (415.1 and 316.3 mm) in 2016 and 2017, respectively. Among mulch and irrigation levels, the total water use was more in non-mulched crop (M2) and under IW/CPE=1.00 (I1).The yield attributing characters under D2 were statistically at par with D1 and significantly higher than D3 and among mulch and irrigation treatments in M1 and I2. During 2016, difference in grain yield under different dates of sowing was found to be non-significant. During 2017, the grain yield under D2 (52.37 q/ha) was at par with D1 (50.86 q/ha) but was significantly higher than D3 (41.04 q/ha). During 2017, among mulch levels, the grain yield was significantly higher in mulch applied crop (50.71 q/ha) as compared to non-mulched crop (46.14 q/ha). The water, heat and radiation use efficiency of maize was also found to be higher under D2, I2 and M1, during both the years. The priestley-taylor method gave higher ETo in all three dates of sowing and was closer to open-pan evaporation except in first date of sowing during 2016, in which ETo was higher in FAO-56 (602.4 mm). The crop coefficients calculated by Papadakis method were comparatively higher as compared to that calculated by other methods. Good agreement was observed between actual and simulated yield (R2=0.77 each) and water productivity (R2= 0.43 and 0.44) during both the crop growing seasons. Simulation results showed that water productivity of maize increased with increase in CO2 concentration and decreased with increase in temperature, but this decrease could be compensated by simultaneous increase in CO2 concentration.
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    ThesisItemOpen Access
    Pathogenic and genetic variability in isolates of Fusarium moniliformeSheld. causing stalk rot of maize (Zea maysL.) and its managemen
    (PAU, 2012) Harleen Kaur; Chander Mohan
    Disease surveys revealed that Fusarium stalk rot was present in all the maize growing areas of Punjab and disease incidence and severity were comparatively high on private company hybrids (31-Y-45 and Double) as compared to public sector hybrids (PMH 1and PMH 2).Maximum disease incidence and severity were found in the district of Hoshiarpur closely followed by Nawanshahar during both Kharif and spring seasons. Frequency of occurrence of Fusarium moniliformeon stalk rot infected plants was highest followed by Macrophomina phaseolina and Cephalosporium maydis.In all, 56 isolates of F. oniliforme were obtained. They were grouped into seven major clusters based on their cultural and morphological characteristics. Pathological behavior of all isolates of F. moniliforme differed on a set of five inbred lines (LM-13, CM-140, CM-143, CML-25 and CM-600) and four maize hybrids (PMH 1, JH 3459, NK 6240 and 31-Y-45). On the basis of multivariate cluster analysis of pathogenicity data, seven clusters were formed and each cluster represented a specific disease reaction to a particular hybrid/inbred tested. The isolate Fm 10 was found most pathogenic with average disease index (ADI) of 66.6 per cent hereas,the isolate Fm 45 was found least pathogenic with ADI of 42.5 per cent. Cross infectivity studies revealed that the maize isolate of F. moniliforme was pathogenic to wheat and basmati rice and non-pathogenic to peas, non-basmati rice and sugarcane. Likewise, sugarcane isolate of F. moniliforme was found most virulent; wheat and rice isolates moderately virulent and basmati rice and pea isolates were comparatively less virulent on maize. Out of twenty RAPD markers used to study the molecular variability of all 56 isolates of F. moniliforme, 18 showed amplification with a total of 220 amplified fragments. The PIC value was found lowest in primer OPT-9 and highest in primer OPT-12. Dendrogram based on molecular data generated by 18 RAPD primers showed six complete clusters and one independent lineage. When the clusters obtained by morphological, pathological and molecular data werecompared, no association could be obtained among cultural characteristics, virulence pattern and RAPD pattern. Studies of antagonistic potential of native biocontrol agents against F.moniliforme revealed that richoderma harzianumisolate, Th1 showed strong mycoparasitism by completely covering the mycelium of pathogen within 4 days of incubation under in vitroconditions. Two methods of application viz. seed treatment with Th1 @ 20 g/kg seed and amending the soil with FYM supplemented with talc based formulation of T. harzianum found promising in pot house studies, were further tested under field conditions. The maximum disease control and seed germination were obtained when soil was broadcasted with FYM supplemented with T. harzianum@ 2 kg talc/q FYM and amendment of soil with FYM supplemented with T. harzianum@ 100g/hill, respectively. Maximum increase in grain yield was obtained in FYM supplemented with T. arzianum@ 100g/hill