Tauqeer Ahmad Yasir

Influence of Various Tillage Practices on Soil Physical Properties and Wheat Performance in Different Wheat-based Cropping Systems

Excessive tillage in conventional agriculture systems may cause plough pan, which alters soil physical properties, and thus adversely affects the crop growth and productivity. This study was conducted to monitor the effect of different tillage practices in wheat-based cropping systems on soil physical properties, allometry and grain yield of wheat. Wheat was planted in different cropping systems (viz. fallow-wheat, rice-wheat, cotton-wheat, mungbean-wheat and sorghum-wheat with zero tillage, conventional tillage, deep tillage and on two types of beds (60/30 cm with four rows) and (90/45 cm with six rows). Interaction between different tillage practices and cropping systems had significant effect on soil bulk density and total porosity, wheat allometry and grain yield. Minimum bulk density tied with higher total porosity was recorded in both types of bed sowing followed by deep tillage. This improvement in soil physical properties caused improvement in leaf area index and duration, specific leaf area, crop growth, and net assimilation rates. As a result, the productivity of bed sown wheat was better; however, grain yield of zero tilled wheat was low due to poor crop growth and net assimilation rate. Wheat productivity was substantially low when planted after sorghum; nonetheless, and was quite high when sown after mungbean. In crux, wheat planting on beds after mungbean is the best option considering the long-term environmental sustainability of wheat-based cropping systems.

Single nucleotide polymorphisms in TaER genes and their association with carbon isotope discrimination in wheat genotypes under drought

Candidate gene association studies implicate the detection of contributing single nucleotide polymorphism (SNP) for the target traits and have been recommended as a promising technique to anatomize the complex characters in plants. The ERECTA gene in plants controls different physiological functions. In this study, we identified SNPs in 1.1 kb partial sequences of TaER-1 and TaER-2 of wheat (Triticum aestivum L.). Thirty-nine SNPs were identified in the coding regions of TaER-1 gene in 33 wheat genotypes, of which 20 SNPs caused non-synonymous mutations while 19 SNPs produced synonymous mutations; 31 SNPs were located in the coding regions of TaER-2 gene in 26 genotypes, of which 18 SNPs caused non-synonymous mutations and 13 SNPs caused synonymous mutations. In addition, 32 SNPs in TaER-1 and 9 SNPs in TaER-2 were also identified in the non-coding regions. Moreover, the significant genetic associations of SNPs of TaER-1 and TaER-2 genes with carbon isotope discrimination, stomatal conductance, photosynthetic rate, transpiration rate, intrinsic water use efficiency (iWUE), leaf length, leaf width, stomatal density, epidermal cell density, and stomatal index were noted in wheat genotypes. This study confirms the importance of TaER-1 and TaER-2 genes which could improve iWUE of wheat by regulating leaf gas exchange and leaf structural traits. These identified SNPs may play a critical role in molecular breeding by means of marker-assisted selection.

FOLIAGE APPLIED ZINC IMPROVE THE GROWTH AND PRODUCTIVITY OF WHEAT

A field experiment was conducted to investigate the effect of foliar application of zinc fertilizer on the growth, yield and yield components of wheat. Experiment was laid out in a factorial randomized completely block design consisting of twelve treatments with three replications. The levels of zinc sulfate were 0 (control water spray), 0.25% solution of zinc, 0.5% solution of zinc, 0.75% solution of zinc. Levels of zinc sulfate were applied at tillering, booting and tillering × booting stages of growth. Results revealed that highest values for relative growth rate, leaf area index, net assimilation rate, total number of fertile tillers m -2 , plant height, number of spikelets spike -1 , spike length, grain spike -1 , 1000 grains weight, grain yield, straw yield, biological yield and harvest index was observed with 0.5% solution of zinc sulfate. Foliar application of 0.5% solution of zinc sulfate (at the time of tillering booting) appeared to be the best doze for wheat crop under Multan conditions.