限量灌溉和遮阴对干热区小粒咖啡生长、光合及产量的影响

Effects of limited irrigation and shading on growth,photosynthesis and yield of Coffea arabica in dry-hot area

为了探明云南干热河谷区小粒咖啡高产的灌溉和遮阴优化模式,设置了3个灌水处理(高水WH,中水WM和低水W_L)和4个遮阴处理(S_H,遮阴度95%;S_M,遮阴度75%;S_L,遮阴度55%;S0,自然光照),研究了不同的灌水和遮阴对小粒咖啡生长、光合特性日变化、叶片水分利用效率、叶片光能利用效率和产量的影响.结果表明,与W_L相比,增加灌水分别提高了株高和新枝长度5.60%~12.39%和10.83%~19.50%,叶片水分利用效率、叶片光能利用效率和干豆产量分别提高了16.98%~36.79%,61.64%~121.95%和47.27%~120.76%.与S0相比,S_L的日均净光合速率、气孔导度、叶片水分利用效率、叶片光能利用效率和干豆产量分别增大了5.85%,10.80%,6.64%,28.51%和20.05%.与W_LS0相比,增加灌水和遮阴,能同时增大叶片水分利用效率、叶片光能利用效率和干豆产量13.94%~44.47%,7.96%~231.04%和44.55%~143.41%,处理W_HS_L的干豆产量最大,为6 131.84 kg/hm^2.因此,从最佳产量角度考虑,干热区小粒咖啡的水光耦合模式为W_HS_L组合.

In order to clarify the optimal irrigation and shading modes for a high yield of Coffea arabica in hot and dry valley area of Yunnan, three irrigation and four shading schemes are established for field experiment and the coupling effects of water and light on growth, net photosynthetic rate, water use efficiency, light use efficiency and yield of Coffea arabica are studied. The three irrigation schemes are WL, WM and WH and four shading schemes are SO -no shading, SL -55% shading, SM -75% sha- ding and Sn -95% shading. The results show that an increased irrigation can improve plant height and new branch length by 5.60% - 12.39% and 10. 83% - 19.50%, and enhance water use efficiency, light use efficiency and dry bean yield by 16.98% - 36.79%, 61.64% - 121.95% and 42.27% - 120. 76%, respectively, compared with WE. Compared with So, the average daily Pn, Ci, water use efficiency, light use efficiency and dry bean yield of SL have been increased by 5.85%, 10. 80%, 6. 64%, 28.51% and 20. 05%, respectively. Compared with WLSo, the increased irrigation level and shading area can improve water use efficiency, light use efficiency and dry bean production by 13.94% -44.47%, 7.96% -231.04% and 44. 55% - 143.41% simultaneously. It was noted that WuSL can lead to the largest dry bean production, as 6 131.84 kg/hm2. Therefore, from the highest yield point of view, WHSL should be the optimal mode of water - light coupling for Coffea arabica in hot and dry valley area.