The effect of plastic mulch and row covers on the growth and physiology of cucumber

Abstract

To determine the effectiveness of black plastic mulch alone and in combination with row covers, on growth and physiological changes of cucumber plants, 6 treatments were established in a randomised complete block design with 4 replications: bare soil (control); black polyethylene mulch alone (B); B plus a clear cover of perforated polyethylene (BRCP); B plus a white cover of perforated polyethylene (BRWP); B plus an Agribon cover of polypropylene (BRA); and B plus a Kimberly farm row cover (BRK). For the plants grown with mulch or mulch combined with row covers, the dry weight of leaves 50 days after seeding (DAS), and the dry weight of whole plants (at 50 and 110 DAS) were significantly ( P <0.05) different from the control. Early yields of treatments B, BRCP, BRWP, BRA and BRK were 2.1, 1.9, 2.6, 1.9 and 2.4 times higher than the control, which yielded 10 t/ha. Total yields were increased by 9.7, 15.4, 19.8, 14.9 and 20 t/ha, over the control which yielded 104 t/ha. Increases in plant dry weight explained the changes in yield. Stomatal conductance may explain in part, the increase in photosynthetic rate, but may not explain yield increase.