Impact of Rows Pacing and Weed Management Strategies on the Tomato (lycopersicon esculentum mill.)

Abstract

Field trials on the impact of row spacing and weed management strategies on tomato were conducted in 2012 and 2013 at the Research Farm of the University of Agriculture, Peshawar, Pakistan using a randomized complete block design with split plot arrangement with three replications. The main plots of the experiment comprised of three varying inter row spacings (40, 60, and 80 cm), and ten different weed management strategies including polyethylene (white), polyethylene (black), wheat straw @ 1 kg, saw dust @ 1 kg, paper mulch @ 1 kg m-2, fenoxaprop-p-ethyl @ 2 kg a.i., s-metolachlor @ 1.5 kg a.i., pendimethalin @ 1.44 kg a.i. ha-1, a hand weeding and a weedy check were kept into the subplots. Data were recorded on weed parameters i.e. weed density m-2 (20 , 40, 60 days after transplanting), fresh and dry weed biomass (kg ha-1), and on crop parameters including plant height (cm), number of branches plant-1, days to first flowering, days to first fruiting, number of fruits plant-1, fruit weight plant-1 (kg), leaf area (cm2), leaf area index (LAI), and cumulative fruit yield (kg ha-1). The weather conditions in either year of study were different, the mean temperature was 3°C higher in 2012 as compared to 2013. Similarly, the precipitation received was also different, thus the differential crop weed interactions over the years were witnessed, despite the crop was regularly irrigated as and when required. However, the mutual effect of the crop and weeds on each other was somewhat consistent in the two years of the study. During both the years, the effect of row spacing was significant on all the crop and weed parameters. Among the row spacing in 2012, the highest values for weed density m-2 at 20, 40, and 60 DAT (13.29, 23.92, 35.88 m-2), fresh and dry weed biomass (1219 and 870 kg ha-1), days to first flowering (40.22) and days to first fruiting (55.21) were recorded in 80 cm row spacing; highest number of branches plant-1 (9.09), total number of fruits plant-1 (19.71), fruit weight plant-1 (1.97 kg) and total fruit weight (12.12 t ha-1) were found in 60 cm row spacing, while largest plant height (82.47 cm), leaf area (577.68 cm2) and leaf area index (3.14) were noted in 40 cm row spacing. For the weed management strategies in 2012, the highest values were deciphered for weed density at 20, 40, 60 DAT (14.33, 24.47, 36.01 weeds m-2), fresh and dry weed biomass (1603 and 1145 kg ha-1), plant height (84.67 cm) in the weedy check plots and the lowest weed densities at 20,40 and 60 DAT (5.26, 8.90, 13.04 weeds m-2), fresh and dry weed biomass (510, 364 kg ha-1) and plant height (70.62 cm) were recorded in hand weeded plots. However, the number of branches plant-1 (10.40), total number of fruits plant-1 (23.33), fruit weight plant-1 (2.33 kg), leaf area (494.97 cm2), leaf area index (3.05) and fruit yield (13.73 t ha-1) were the highest in hand weeded plots and the lowest number of branches plant-1 (6.16), days to first flowering (37.1 days) and first fruiting (49.4 days), total number of fruits plant-1 (11.54), fruit weight plant-1 (1.15 kg), leaf area (464.69 cm2), leaf area index (2.20), and fruit yield (6.75 t ha-1) were recorded in weedy check treatments. A similar trend of the row spacing and weed control treatments effect on crop and weed parameters was found in 2013. The highest values in 2013 for weed density m-2 at 20, 40 and 60 DAT (16.61, 29.90, 44.85 m-2), fresh and dry weed biomass (1524 and 1088 kg ha-1), days to first flowering (45.2) and days to first fruiting (54.2) were recorded in 80 cm row spacing, highest number of branches plant-1 (10.11), total number of fruits plant-1 (24.64), fruit weight plant-1 (2.19 kg) and total fruit weight (15.15 t ha-1) were found in 60 cm row spacing, while largest plant height (91.63 cm), leaf area (686 cm2) and leaf area index (3.6) were noted in 40 cm row spacing. The highest values were achieved for weed density at 20, 40, 60 DAT (17.92, 30.58, 45.01 weeds m-2), fresh and dry weed biomass (2004 and 1431 kg ha-1), plant height (94.07 cm) in the weedy check plots and the lowest weed densities at 20,40 and 60 DAT (6.58, 11.13, 16.30 weeds m-2), fresh and dry weed biomass (638, 455 kg ha-1) were recorded in hand weeded plots for the weed management strategies in 2013. The performance of plastic mulches was second best after hand weeding which were followed by the herbicides in both the years in terms of weed control and yield enhancement. It is thus concluded that 60 cm row spacing integrated with hand weeding and black plastic mulch could be a best integrated approach for weed management in tomato which is environment friendly and economical weed management that is recommended for harvesting optimum tomato yields in Peshawar valley, Pakistan.