No abstract

Increasing crop productivity in semiarid areas is essential for ensuring future food security. We hypothesized that crop yield could be increased by using plastic film mulching to reduce evaporation and increase plant density. A 3-yr field experiment was conducted on the Loess Plateau of China to evaluate the effects of soil temperature and water content on maize (Zea mays L.) grain yield (GY) and water-use efficiency (WUE). Film mulching promoted maize growth and development by increasing the soil temperature and water content, particularly during the early growth season. At harvest, the mulched treatments had higher kernel numbers per ear (KN) and greater 1000-kernel weight (KW) than non-mulched treatment. Furthermore, mulching allowed the optimum plant population to be increased from 65,000 to 85,000 plants ha -1 . Compared with mulching for the entire growing season, removing the film at the silking stage decreased the plant senescence rate and slightly increased the final KN and KW, thus further increasing the GY by 0.6 to 1.2 Mg ha -1 . Although the WUE showed no significant difference among the three mulched treatments (34.0-47.2 kg ha -1 mm -1 ), these values were markedly higher than that in the non-mulched treatment (20.3-29.6 kg ha -1 mm -1 ). We conclude that film mulching together with increased plant density can increase semiarid maize yields and water-use efficiency.

No abstract

No abstract

Film mulching is a very common technique in agriculture worldwide, but few studies have focused on the dry matter (DM) and N accumulation of mulched crops. Understanding the grain yield (GY) associated with DM and N accumulation is essential for improving crop production. We conducted a 3‐yr field experiment with six N fertilizer rates (0, 100, 200, 250, 300, and 400 kg ha−1) in the semiarid climate of northwest China to determine the GY and DM and N accumulation of film‐mulched maize (Zea mays L.). The results showed that relatively high GYs (13.1–15.1 Mg ha−1) were obtained using N fertilizer rates of 200 to 400 kg ha−1 in the 3 yr despite large year‐to‐year differences in rainfall. When the N rate was below 250 kg ha−1, the GY, DM, and N accumulation increased significantly as the N fertilizer rate increased. A linear‐plateau model best described the relationship between the GY and the DM and N accumulation during the pre‐silking stage and a linear model the relationship during the post‐silking stage. We conclude that optimizing N management to improve DM and N accumulation (especially post‐silking) is the key to ensuring a high yield of film‐mulched maize.