Effects Of Three Plant Growth Regulators On Carbon Metabolism Physiology, Yield And Quality Of Potato

During the two years of2011-2012, some field experiments were conducted with five potato（Solanum tuberosum L.）cultivars such as ‘H-212’,‘Favorita’,‘Atlantic’,‘ZDB’,‘K13’. And weused three regulators,‘Uniconazole(S3307)’,‘Choline chloride(Cc)’and ‘Diethyl aminoethyl hexanoate(DTA-6)’ by foliar application on the leaves. In this study, the aim of this experiment was to comparethe change of PGRs on the activities of some enzyme such as invertase, amylase etc. in the leavespetiole,phloem, stolon and tuber of potato, investigate the differences of physiological characters suchas sucrose,starch etc. in potato plant, research the effects of PGRs on yield and quality structure. Wepreliminary want to proven the influence of PGRs on carbon metabolism by this study, and it canprovide academic theories for usage of PGRs for higher yield, better quality, and more efficiencyproduction of potato. The main results were:1. Plant growth regulators can regulate the photosynthetic traits of potato, DTA-6and Cc treatmentare better, effect of treatment with S3307followed. The content of Chla and total chlorophyll wereincreased with DTA-6and S3307at the late sampling. while these three treatments can significantlyimprove the water use efficiency at the beginning of flowering and stomatal conductance at the periodof flowering. In addition, the Cc treatment can significantly increase the transpiration rate.2. The content of glucose was increased in leaves with spraying plant growth regulators, Cctreatment is better, DTA-6treatment followed. For fructose, DTA-6and S3307treatment are better.3. All these three treatments can increase the sucrose synthase activity in leaves, S3307treatment ismainly in the tuber formation stage, Cc and DTA-6treatment are mainly at the starch accumulationperiod, which Cc treatment is better, DTA-6followed. In addition, Cc and DTA-6may also improve thesucrose phosphate synthase activity in leaves at the starch accumulation period, which Cc treatment isbetter.4. When spraying PGRs at the beginning of flowering stages, all treatments can increase the contentof sucrose in leaves at late of sampling, whereas Cc treatment is preferably, DTA-6treatment is weak.Further, Cc treatment can also improve the activities of neutral invertase and invertase at the sameperiod. In addition, all treatment can also reduce the starch content and the amylase activity in leavesof “H-212” potato, of which Cc treatment is best, DTA-6treatment is followed. In the other hand, Ccand DTA-6treatment can increase amylase activity in leaves of “ZDB” potato. And spraying PGRs atthe stages of flowering, these three treatments can increase the content of fructose in leaves at late ofsampling, but without sucrose. DTA-6treatment can increase amylase and invertase activity in leavesof “H-212” potato, as well as Cc with “K13” potato.5. Each treatment can regulate the carbon metabolism assimilate in transport organs of potato. Thecontent of reduced sugar can be reduced by Cc treatment, but it can increase the sucrose content in thepetiole. S3307treatment has the same effect with Cc in the phloem. In addition, DTA-6treatment canreduce the content of soluble sugar, Further, both DTA-6and Cc can also increase the content of sucrose content in the stolon. As a whole, Cc and DTA-6treatment can increase the content of sucrosein the transport organs of potato, which is better to Cc treatment, DTA-6treatment is followed.6. All treatments can regulate some enzyme activities of carbon metabolism in transport organs ofpotato. At late of sampling, Cc and DTA-6can improve the neutral invertase activity in the petiole of“H-212” potato, but also reduce it of “ZDB” potato. Each treatment has little effect on the petioleamylase activity, but can reduce the activity of amylase in the phloem. In the other hand, Cc treatmentcan improve the neutral invertase activity in the stolons of “H-212” potato, S3307and DTA-6treatmentreduce it in the stolons of “ZDB” potato.7. All treatments can regulate some enzyme activities of carbon metabolism and the content ofcarbon metabolism assimilate in storage organs of potato. When spraying PGRs at the beginning offlowering stages, Cc and DTA-6can improve the starch phosphate synthase activity in the tubers of“H-212” potato at late of sampling, in which Cc treatment is best. But each treatment has negligiblyeffect with the starch phosphate synthase activity in the tubers of “ZDB” potato. In the other hand, Ccand DTA-6treatment can improve the invertase activity in the tubers, and Cc treatment reduces theactivity of amylase in the tubers at the starch accumulation period. And spraying PGRs at the stages offlowering, these three treatments can increase the content of starch and sucrose in tubers at late ofsampling, but without fructose, which DTA-6treatment is better. S3307can increase amylase andinvertase activity in tubers of “K13” potato.8. When spraying PGRs at the beginning of flowering stages, DTA-6can significantly increase theyield of the heavy potato with “H-212” and “H7”, and it also can improve the quality characters suchas starch, vitamin C. Cc can significantly increase the yield of the heavy potato with “ZDB”, and itcan increased the content of starch and reduced sugar in tuber. S3307can significantly increase theyield of the heavy potato with “H-212” potato. And when spraying at the stages of flowering, DTA-6can significantly increase the yield of the heavy potato with “ZDB”,“Atlantic”, and “K13”, and Cccan significantly increase the yield of the heavy potato with “Atlantic”.9. In one words, DTA-6and Cc treatment can improve the formation of carbon metabolites andimprove the content of sucrose in the transport organs, improve the tuber starch phosphate synthaseand invertase activity, reduce the amylase activity in the tubers, they can also improve the heavypotato production and improve the quality. On the whole, we believe that Cc treatment is the best. Inaddition, the special period, it is worth noting that the application test results showed that thebeginning of flowering spraying effect is better.