1. Introduction:

Chickpea is very useful as well as important pulse crops of India, which are cultivated under conserved soil moisture and irrigated situations. The production of chickpea has fallen due to several constraints such as biotic and abiotic factors. Among the biotic constraints wilt, dry root rot and blight are the chief constraints in Karnataka. In adding to that, the weeds also result in main damage in yield by challenging for space, nutrients, water and light. Poor weed supervision is one of the most important yield preventive factors in chickpea. Weeds should eliminate plant nutrients from soil as compare to crops. Under rain fed condition, weeds use maximum water and increase severity of drought and results in a less crop yield. Maximum weed species which are faster growth in nature and higher than chickpea and prevent crop growth, absorbs sunlight, and disturb photosynthesis and plant productivity adversely (Rao 2000). Normally, controlling of weeds farmers do physical weeding. But with the increase in labor cost and scarcity of labor, manual weed control has become a difficult task in chickpea, chickpea is very susceptible to weed competition and weeds affect up to 75% yield loss (Chaudhary et al., 2005). Weed management in chickpea is an key component of plant protection thus increasing production potential of the crop. Therefore, the work was assumed to detect the effect of various weed management practices on productivity of chickpea under Doon valley conditions.

 2. Materials and Methods:

A field experiment entitled “Integrated Weed management in Chickpea (Cicer arietinum L.) Under Doon valley condition” was conducted during rabi season 2017-18 at, Doon (P.G.) College of Agriculture Science and Technology, Selaqui, Dehradun (Uttarakhand). The soil of the experiment field was sandy loam in texture, low available nitrogen (115.20 kg ha^-1), medium available phosphorus (17.92 kg ha^-1) and high potassium (119.0 kg ha^-1) and neutral pH 7.4. The experiment was carried out in Randomized Block Design with three replications. The treatments consist of eleven weed management practices Viz. Different weed management practices were done as per the treatments in the experiment. are Pendimethalin 30 EC PE @ 700 g ha^-1,(T₁) Pendimethalin 30 EC Pre-emergence  @ 0.700 kg a.i. ha^-1 fb then one hand weeding at 30 DAS  (T₂),then use  Oxyfiurofen 23.5 EC Pre-emergence @ 0.90 kg a.i. ha^-1 (T₃), and Oxyflurofen 23.5 EC Pre-emergence @ 0.90 kg a.i. ha^-1 then one hand weeding at 30 DAS (T₅), Metribuzin 70% WP PE @ 0.200 kg a.i. ha^-1 fb one  hand weeding at 30 DAS (T₆), Imazethapyr 10%  SL EPoE @ 0.25 kg and  0.050 kg a.i ha^-1 at 20 DAS in (T₇) & (T₈) Then  One hand hoeing at 15 DAS + one hand weeding at 30 DAS (T₉), Weed free up to 60 DAS (T₁₀) Weedy check (T₁₁). The chickpea variety Pant G-186 was grown at test crop on November 26, 2017 and harvesting April 12, 2018.Weed control efficiency (WCE) was calculated by the following formula.

      WCE (%) =WCC-WCTWCCX100

3. Results and Discussion:

3.1. Effect on Weeds:

The experiment field was dominated Cynodon dactylon, Phalaris minor, Bracharia mutica, Cyperous rotondus of monocot weeds and Convolvulas arvensis, Chenopodium album, Parthenium hysterophrus, Melilotus indica of dicot weeds during of growing season, similar result were reported by Ratnam et al., (2011). The weed density and weed dry weight was significantly differ with the Weed free up to 60 DAS recorded significantly lower density of monocot and dicot weeds. At all the treatments Weed free up to 60 days after sowing (T₁₀) gave the best management of monocot and dicot weeds than other treatments because initially weed were controlled by hand weeding 30 DAS and whatever weeds emerged later were effectively removed by subsequent of hand weeding carried out at 60 DAS. This result is similar by Kachhadiya et al, (2009). The weed density and dry weight of monocot and dicot weeds in control plot were significantly the highest than rest of the treatments.

3.2. Weed index and weed control efficiency:

Minimum weed index (0.00 %) and maximum weed control efficiency (Table1) at 30 and 60 DAS and at harvest were observed were observed at hand weeding carried out at 30 and 60 DAS. The lower weed index and higher weed control efficiency of treatment of Weed free up to 60 DAS, higher efficiency of the herbicides at early growth stage and one hand weeding at advanced stage was effective in directing weed dry matter in the various combined approaches of weed management. This result is similar to Ruparelia et al,.(2017).

3.3. Yield attributes and Yield:

The higher plant height of chickpea crop was recorded at 60 DAS and at harvest under the treatment of Weed free up to 60 DAS. Crop dry matter accumulation at 60 DAS, number of pods plant^-1 number of branches and test weight were recorded significantly higher at harvest under treatment weed free up to 60 DAS (T₁₀), Pendimethalin 30 EC Pre-emergence  @ 0.700 kg a.i. ha^-1 fb then one hand weeding at 30 DAS  (T₂), Oxyfiurofen 23.5 EC Pre-emergence @ 0.90 kg a.i. ha^-1 (T₃).

Table 1: Weed density, weed dry weight and weed control efficiency at different days influenced different weed management practices

All Figures are subjected to transformed values to square root (√x+0.5).

Table 2: Weed index, Plant height, Crop dry matter accumulation, number of branches, yield attributes, yield and economics of chickpea as influenced by different weed management practices economics