Effect of Glyphosate , Gramaxon and hand hoeing on productivity of cotton and its associated weeds

Abstract

Weed control study on cotton (V. Lashata) were conducted during growing season 2011 at Hawi AL- Kaneesa (H) and College farm (C) at the Mosul University in Nenava governorate (IRAQ) to determine the effect of seven hand hoeing treatments (hand hoeing after two (T1) , four (T2) and six (T¬3) weeks of seeds cotton emerged , twice hand hoeing (T1+ T2) , (T1 + T3) and (T2 + T3) and un weeded treatment, All there treatments were practericed in herbicide treatment (Glyphosate 6.4 Lai . ha-1, Gramaxon 2.8 Lai . ha-1 and without herbicides) which had sprayed before the initial plowing and furrow. These treatments had done to improve productivity and quality of cotton under the weed control.The results indicated that cotton plants had less competitive with weeds which reflect or reducing cotton yield. Glyphosate and Gramaxon had un significant results in dry weight (DWT) of broad leaves weed, but Glyphosate was reduced the (DWT) of narrow leaf weeds up to 49.7 %. On other hand, the plant height and number of sympodial branches were increased up to (8.6 , 7)% and (15 , 21.5)% respectively for Glyphosate and Gramaxon treatments. Also lint yield was increased up to (37.9 , 35.2)% for the herbicides respec- tively over all locations. Hand hoeing after six weeks of cotton emerged (T3) and twice hand hoeing had reduced the (DWT) of narrow leaf. There was clear evident that treatment (T¬1 + T2) was increased in number of sympodial branches up to 40 % . In general, twice hand hoeing was more superpass than a single hand hoeing in plant height. The best result had obtained from (T1 + T3) and (T2 + T3) for increasing lint yield up to 80.4% and 79.6% respectively. Regarding to the locations, (H) location gave the best result in reducing (DWT) of weed which reflected on increasing lint yield up to 52.9 % if it compeered with (C) location.