Effect of IWM on weed dynamics, dry matter accumulation, yield and economics of turmeric

Abstract

Turmeric (Curcuma longa L.) is one of the important spice crops grown in India in an area of 1.94 Mha with an average production of 9.71 ton and productivity 5 ton/ha (Anonymous 2013). Weed competition is one of the limiting factors for low yield of turmeric. Due to improper weed management, 30-70% yield losses have been reported in the crop (Krishnamurty and Ayyaswamy 2000). Turmeric is a long durational crop takes 8-9 months, therefore, preemergence application of herbicides alone can not control weeds throughout critical crop-weed competition period of the crop and needs an integration of pre-and post-emergence application of herbicide or inter-culture operation in combination with pre-emergence herbicide application. Hence, a field experiment was carried out to suggest a suitable integrated weed management for better production of turmeric.The experiment was carried out during rainy season, 2014 at Birsa Agricultural University, Ranchi, Jharkhand in randomized block design with three replications. The soil of experimental field was sandy loam slightly acidic in reaction (pH 5.9), low in organic carbon (4.2 g/kg) and N (243 kg/ha) while medium in P 19.15 kg/ha and K (188 kg/ha). The turmeric variety 'Rajendra sonia' was planted at 40 x 25 cm spacing on 3 rd July 2014. The recommended dose of FYM at 10 t/ha and 120:60:100 kg/ha NPK was applied. The experiment comprised of 15 treatments ( Table 1). Un-weeded check as hand weeding at 25, 45 and 75 DAP and un-weeded check respectively. All the herbicides alone or in mixture were applied with knapsack sprayer fitted with flatfan nozzle using 600 litres water/ha. Crop growth rate (g/m 2 /day) was calculated by using the following standard formulae suggested by Leopold and Kridemann (1975) between 30-90 and 90-150 DAP -Where, W2 and W1 are plant dry weight at time t2 and t1. Weed floraThe major weeds found in experimental plot, viz. Ageratum conyzoides (L.), Celosia argentea (L.), Acalypha indica (L.) among broad-leaved weeds; Digitaria sanguinalis (L.), Panicum dichotomiflorum among grassy and Cyperus rotundus (L.) among sedges were predominant. Among all the categories broad-leaved dominated (60.4%) followed by grassy (28%) and sedges (11.6%). Effect of weed density and dry matterAmong chemical weed control methods application of metribuzin 0.7 kg/ha PE fb fenoxapropp-ethyl 67 g/ha + metsulfuron 4 g/ha at 45 DAP recorded reduced total weed density at 90 and 150 DAP to the tune of 66.96 and 54.67% compared to hand weeding at 25, 45 and 75 DAP respectively. Similarly, total weed dry matter accumulation was reduced in metribuzin 0.7 kg/ha PE fb fenoxaprop-pethyl 67 g/ha + metsulfuron 4 g/ha at 45 DAP at 90 and 150 DAP to the tune of 44.24 and 52.27% respectively compared to hand weeding at 25, 45 and 75 DAP.The mean dry matter accumulation (g/m 2 ) by total plant parts increased gradually from 30 DAP to 150 DAP and then slightly decreased at 210 DAP. The mean dry matter accumulation at 30, 90, 150 and 210 DAP were 42.8, 345, 570 and 554 g/m 2 . The respective increase...

Integrated Weed Management in Turmeric (Curcuma longa)

“…The control plot had the lowest yield and minimal gross return, and as a result, its BCR was likewise the lowest. According to Bharty et al [34], chemical herbicides produced the highest net return and BCR, followed by straw mulch and hand weeding. Similar findings were made by Anshuman et al [35] who discovered that paddy straw mulching at a rate of 10 t/ha produced the highest gross return (Rs 3,29,000/ha).…”