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Mepiquat chloride (MC) is a plant growth regulator used to manage the rampant vegetative growth of cotton. A two-year field experiment was conducted at the Postgraduate Agricultural Research Station, University of Agriculture, Faisalabad, Pakistan, during 2017 and 2018 to investigate the influence of MC applied at different times on phenology, morphology, lint yield and quality of cotton cultivated using different sowing techniques. MC was applied 50 days after sowing (DAS), 60 DAS and 70 DAS to cotton planted in flat fields (flat sowing), ridges (ridge sowing) and beds (bed sowing). The interactive effect of MC application time and sowing technique did not influence crop phenology, morphology, and lint yield and quality. It was revealed that the crop planted on beds took fewer days to flower (10%) as compared to that on the flat field, and the bed-sown crop produced a higher number of opened bolls (60%) and was characterized by a higher boll weight (32%) and seed cotton yield (50%) in comparison to the flat-sown crop. A late application of MC (at 70 DAS) caused a significant reduction in the time to flowering (8%), with a simultaneous increase in the number of opened bolls (60%), boll weight (32%), ginning out turn (8%) and lint yield (27%) as compared to MC application at 50 DAS. In terms of lint quality, cotton planted on beds had better fiber uniformity (8%) compared to that on the flat field, while MC applied at 70 DAS produced better fiber fineness by 27% in comparison to MC applied earlier. Overall, cotton planting on beds and MC application at 70 DAS may help improve cotton yield and fiber quality and may help in the mechanical picking of cotton. [ABSTRACT FROM AUTHOR]

Water and labour scarcity pushes researchers to explore alternate sowing methods for rice like aerobic direct seeding but weed infestation is the major hindrance to adapt this production system. In our study, mechanical, chemical and cultural approaches were employed as weed control measures. Weed dynamics and yield parameters were recorded and economic analysis was performed. All weed control measures significantly reduced the weed density and weed dry weight as compared to control and improved harvest index. Maximum control in total weed density and total weed dry weight was achieved by hoeing followed by chemical control. The order of treatment groups in decreasing total density, total weed dry matter production and increment in harvest index was as cultural, chemical and mechanical. However, substantially highest net returns (PKR 44,049/) and highest benefit cost ratio (BCR) (1.53) were obtained by post emergence application of Penuxsulam at the rate of 15 g a.i ha-1 followed by hoeing. Inter-culture, mulching technique and Sesbania drummondi intercropping scored 1.19, 1.13 and 1.21 BCR, respectively. Thus, hoeing with hoe (25 and 45 days after sowing) and post emergence application of Penoxsulamat the rate of 15 g a.i ha-1 were most effective, profitable and economical weed control options. [ABSTRACT FROM AUTHOR]

Crop growth and productivity may differ under different sowing methods and planting densities. A field experiment was conducted to evaluate the influence of different sowing methods and planting densities on growth, yield, quality and economic returns of cotton. Sowing methods included pit planting (1 m × 1 m pits), bed planting (75 cm apart beds), ridge planting (75 cm apart ridges) and line sowing with varied inter row spacing (25, 50 and 75 cm). Sowing methods significantly affected growth and yield of cotton. Pit planting imposed maximum increase in plant height (152 cm), number of monopodial branches (4.7) and sympodial branches (22.6) per plant, number of unopened (9.4) and opened bolls (41.1) per plant, and average boll weight (3.0 g) of cotton. However, highest seed cotton yield (2944.5 kg ha-1) was obtained by flat sowing on 25 cm apart rows owing to highest planting density per unit area. Maximum ginning out turn (GOT) (41.6%) was noticed in pit planting of cotton, while, fiber quality was not affected significantly by sowing methods. Economic analysis showed that economic returns and benefit cost ratio (BCR) (1.52) was elevated by flat sowing on 25 cm apart rows. In conclusion, maximum seed cotton yield and economic returns can be acquired by flat sowing with 25 cm apart rows, while, fiber quality is independent of sowing methods. [ABSTRACT FROM AUTHOR]

Insufficient mobilization of pre-anthesis photosynthates from vegetative sources to reproductive sinks during achene growth and development plays a key role in reduced productivity of sunflower. Among different essential plant nutrients, a micronutrient boron (B) is known to have a prominent role in the mobilization of pre-anthesis reserves. A field experiment was carried out to investigate the role of soil applied boron in the mobilization and partitioning of pre-anthesis photoassimilates in early and late sown sunflower hybrid. Treatments were comprised of sowing dates (S) randomized in main plots and different rates of boron (B) randomized in sub plots. Treatments were S1= Normal sowing (Mid-February); S2= Late sowing (1st week of March) and B1= Control; B2= Water spray; B3= 1.5 kg B ha-1 at button stage; B4= 2 kg B ha-1 at button stage; B5= 2.5 kg B ha-1 at button stage; B6= 1.5 kg B ha-1 at ray floret stage; B7= 2 kg B ha-1 at ray floret stage; B8= 2.5 kg B ha-1at ray floret stage. Soil applied boron significantly improved the dry matter accumulation (fresh and dry weight of leaf, stem, head and whole plant) and mobilization of photosynthates, capitulum diameter, number of achenes per head, 1000-achene weight, achene and biological yield. Moreover, achene oil and protein contents also increased by the soil application of boron. Normal sowing date was more effective for mobilization of reserves. However, application of B (2-2.5 kg ha-1) mitigated the adverse effects of late sowing to a considerable extent. [ABSTRACT FROM AUTHOR]

To compare the effect of planting time and N levels on phenology and seed cotton yield of Bt and non -Bt cotton, an experiment was laid out at Students' Farm, University of Agriculture, Faisalabad, Pakistan. Two cotton cultivars; FH-113 (Bt) and CIM-496 (non-Bt) were planted during mid March and mid May using 115, 145 and 175 kg ha-1 N levels. Planting times were placed in main plots, varieties in sub plots and N levels in sub sub plots in randomized complete block design with three replications. All the interactions (sowing date × varieties, sowing dates × nitrogen levels, varieties × nitrogen levels, sowing dates × varieties × nit rogen levels) were non significant for parameters (Days taken to squaring, flowering, first boll splition, vertical and horizontal flower interval, boll maturation period, node above white flower, node number for first fruiting branch, first fruiting branch height, earliness index, number of monopodial and sympodial branches per plant, average boll weight per plant, seed cotton yield kg ha-1) under discussion except variety × sowing date for seed cotton yield. Mean values for various phenological events like days taken to squaring, first flower and first boll splition, BMP (boll maturation period), first fruiting branch height (cm), first fruiting branch node number and node above white flower varied invariably between Bt and non Bt sown at different times. Vertical as well as horizontal flower intervals remained unaffected. Maximum seed cotton yield was recorded in FH-113 at mid March planting and minimum in CIM-496 at mid May planting. A N level of 145 kg ha-1 gave maximum seed cotton yield against the minimum with 115 kg ha-1. It was concluded that performance of Bt cotton was better in both mid March and mid May planting with respect to seed cotton yield per hectare. [ABSTRACT FROM AUTHOR]