Effect of no-till straw mulching system on water productivity and performance of potato -

Abstract

Field and green house experiments were conducted during the spring and fall semesters of 2014-2015 to evaluate the effects of different surface barley straw mulch (25, 50 and 75t-ha) on potato growth under a no-till system and to examine the response of potato to different irrigation regimes [120percent, 100percent, 80percent and 60 percent evapotranspiration (Eto)] with or without the surface mulch (till and no-till system). The results of the field experiment showed that the till potato (0t-ha mulch) under the four irrigation treatments significantly enhanced the shoot height and plant number, 35 days after planting potatoes (DAP). While, at 45 DAP, results showed that only plant number in till potato at 75-ha was significantly higher than that of no-till potato at all tested mulching rates (25, 50 and 75 t-ha) under 120percent, 80percent and 60percent Eto. Also, results showed that no-till potato at 75t-ha at 60percent Eto significantly reduced potato shoot number at 45 DAP compared to till (0t-ha). However, shoot number increased with time in no-till potato. For example, the shoot number in all no-till treatments at 80percent and 100percent were significantly not different from each other; the number remained at 75 DAP. Leaf number was high in till potato early in the growing season. However, it increased with time. Root and shoot dry weights were high in till potato (0t-ha mulch) at various irrigation regimes, compared to all no-till treatments at 35 DAP. However, both increased with time. The highest shoot dry weight was observed in no-till potato at 25t-ha at 80percent and 120percent. In regards to potato yields, results showed that all treatments had no negative effect on the total number of tubers except for the no-till potato at 75t-ha at 100percent Eto. No-till potato at 25t-ha at 100percent Eto gave the highest number of tubers. All no-till potato treatments at various irrigation rates significantly increased marketable yield in comparison to the till potato. Marketable yield was the highest with the no-till potato at 75 t-ha at 120percent Eto. The highest total yield observed wa