Effect of weed management and sulphur on nutrient content and uptake by weeds and soybean

Abstract

A field experiment was undertaken to study the effect of weed management and sulphur nutrition on nutrient content and uptake by weeds and soybean during kharif 2009. The results revealed that application of two hoeing and weedings and imazethapyr 100 g/ha+ H&W at 40 DAS recorded maximum seed yield (1475 and 1395 kg/ha, respectively). Two H&W significantly reduced the weed growth and nutrient uptake by weeds, there by increased the nutrient (N, P and S) uptake by crop. Application of 40 kg S /ha significantly recorded the highest seed yield. This also increased N, P and S content and their uptake by soybean and weeds.Key words: Chlorimuron ethy1, Imazethapyr, Hoeing, Sulphur nutrition, Weed management, Weeding.Soybean [Glycine max (L.) Merrill] is a crop of multiple qualities as it is both a pulse and oilseed crop. It is third largest oilseed crop of India after rapeseed-mustard and groundnut. Inspite of its high yield potential (4.5 tonnes/ha) its productivity is much less in india (0.95 ton/ha) than the world average of 2.3 tonnes/ha (FAI, 2006). Being a Kharif season crop, it suffers from severe infestation of weeds and rob it of essential nutrients, space and moisture, causing substantial loss in yield (33-55 %) depending on the weed flora and density of weeds (Kewat, et al.2000). The effective and economical weed control may not be possible through mechanical means due to heavy and continuous rains in kharif. Hence, use of herbicides offers an alternate method to manage weeds in such situation. The sowing time for soybean in rainy seasons is very short and farmers give first preference to sow the crop rather than to use soil applied herbicides for weed control. Under such situation post-emergence herbicides remain the only viable option needs to be explored as an effective and economical method of weed control.It is well known fact that weeds through competition with crop deprive crops of limited essential recourses, prominent among which are nutrients. More over weeds grow faster than the crop plants and absorbed the nutrient earlier resulting into lack of nutrients in general and sulphur in particular for the growth of plants. Thus, control of weeds at appropriate time increase the nutrient use efficiency. Under such situations use of post-emergence herbicides in conjunction with sulphur nutrition needs to be explored as an effective and economical method for obtaining better yield of soybean.

Weed Management through Imidazolinones in Pigeon Pea (Cajanus cajan L.)

“…Among herbicidal treatments, significantly higher nitrogen (1.245%), phosphorus (0.185%) and potassium (1.590%) content in the stalk of pigeon pea was observed in treatment T 14 over alone application of imidazolinones either applied PRE or POE. These results are in contrary with the findings of Dhaker et al (2015) who reported that weed management did not affects the nutrient content of seed and haulm of soybean.…”

Production of Fenugreek (Trigonella foenum-graecum) as Influenced by Weed Management Practices and Vermicompost Application

“…The increase in seed and haulm yield with application of vermicompost might be due to better availability of nutrients in the soil, nutritional status of the crop and increased accumulation of photosynthates and their remobilization to reproductive parts of the plants, being the closest sink and hence, resulted in increased flowering, fruiting and seed formation. Thus, such results also corroborate with the findings of Singh and Singh (2005), Dubey et al (2012) and Dhaker et al (2015).…”

Impact of Weed Control Measures on Soybean (Glycine max L.) under Kymore Plateau and Satpura Hills

“…, respectively) and proved significantly superior to all the treatments (Table 2), except chlorimuron-ethyl 24 g + mechanical weeding (40 DAS). [19] also supported the findings. The crop under weed free plots attained lush growth due to elimination of weeds from inter and intra row spaces besides better aeration due to manipulation of surface soil and thus, more space, water, light and nutrients were available for the better growth and development, which resulted into superior yield attributes and development, and consequently the highest yield.…”