Study On The Effects Of Water On Yield And Quality Development Of Chili Pepper(Capsicum Annuum L. Var. Acuminatum Fingern)

In order to study on the water requirement and water demand of Xinjiang chili pepper, carry moisturegradient experiment under conditions of field condition and anti-canopy drip pot. The field trials wasrandomized block whick repeated for two years. It set up three water gradients，the year of2011was（W1-4140m³/hm²ï¼ŒW2-3600m³/hm²ï¼ŒW3-3060）and the year of2012was（W1-4500m³/hm²ï¼ŒW2-3600m³/hm²ï¼ŒW3-2700m³/hm²ï¼‰. In pot experiment, the soil moisture were set for45%,55%,65%,75%,85%,95%, completely random order and planted20pots per treatment. The responses of in the plants growth,growth target, physiological measure, photosynthetic characteristics, fluorescence parameters，yield andquality were investigated. The results of this experiment showed that:The chili pepper was under field conditions: The plant height and stem diameter of chili pepper wererestrained under the treatment W3. The stem diameter was no significant differences between thetreatments W1and W2. But the treatment of W1can promote the growth of height. The root cap ratio ofthe W1was lower than the W2and W3and there was no significant difference among them.The contents of MDA, proline and the SOD enzyme activity of W3were significantly higher than thatof W1and W2. The soluble protein content of W1and W2was higher in seeding period andbeginning-flower stage, but it was significantly lower than that of W3in later period. The contents ofsoluble sugar under the water treatment W1and W2were higher in the seeding period andbeginning-flower stage and lower in full-bloom period and fruiting period. The content of soluble sugarunder the water treatment W2were the highest in the fruit expanding period. The relative electricalconductivity under the treatment W1was the highest in the period of beginning-flower, the W3wassignificantly higher than the W1and W2in the later stages. The POD enzyme activity of W2was thelowest and that of W3was the highest during the whole growth period. The CAT enzyme activity of W2was the lowest during the whole growth period.The net photosynthetic accumulation, light saturation point, CE, AQY, CO₂saturation point, ΦPSâ…¡,and qP of W2were higher than that of W1and W3. The light compensation point, CO₂compensation pointand NPQ of W2were significantly lower than that of W1and W3. The yield of W2was the highest. Thecontents of capsaicin was W1>W3>W2. There were no significant different among the treatments ofcapsanthin. The capsaicin development time of W2was earliest and the W3was latest.The chili pepper was under potting conditions: The height among the treatments were95%>65%75%>85%>55%>45%. And the stem diameter among the three treatments was rathersignificantly different,65%75%>85%>55%>45%>95%. The fresh weight and dry weight are the highest ofthe treatment85%. The root cap ratio is the highest of the treatment85%and95%.The MDA content of the treatment95%was significantly higher than the other treatments in theperiod of seeding, beginning-flower and full-bloom and the treatment of45%was the highest. And theMDA content of65%was at a low level during the whole growth. The soluble protein content of65%wasthe lowest. The content of proline, the relative electrical conductivity, SOD enzyme activity, CAT enzyme activity and POD enzyme activity were the lowest among the treatments65%-85%. The content of solublesugar was the lowest under the treatment of75%.The Pn of75%and85%was highest, the net photosynthetic accumulation of85%was highest and45%was lowest during the whole growth. The light saturation point of85%was significantly lower thanthe other treatments. The leaves of chili pepper were not suppressed photoinhibition and the ΦPS â…¡washigher among the treatments65%-85%.The yield of75%and85%and the capsaicin content of65%was the highest. The capsanthin of45%was the lowest and there were no significant different among the treatments. The capsaicin developmenttime is the latest of65%among the six treaments.All of above showed that: the treatment of W2was best for the growth of chili pepper under felidconditions in Xinjiang ShiHezi. We can choose the treatment of W3if it was in semiarid area. The soilmoisture content was65%-85%of the saturation field capacity was best for the growth of chili pepperunder potting conditions.