Study On The Dormancy Characteristics Of A. Albus Seeds

Amorphophallus is the only economic crop that has been found so far in large quantities in the synthesis of glucomannan.Glucomannan is a kind of soluble half fiber,which is a high quality dietary fiber and the main ingredient of konjac flour.It has important health functions such as"three high"and improving intestinal microflora.And A.albus glucomannan has high content,white color and good quality.At present,A.albus is mainly propagated mainly by corms and rhizomes.It has long been asexual propagation,and its seed has been seriously degraded,resulting in the decline of disease resistance,and the quality and yield are all seriously affected.Using the seeds of A.albus to reproduce,not only can improve the reproduction coefficient,give play to the heterosis,but also reduce the spread of the pathogen and improve the resistance of the konjac.However,the basic characteristics of A.albus seeds were not systematically studied.In addition,under natural conditions,the seeds of A.albus were found to have long dormancy period,low germination rate and irregular seedling emergence,which became the main limiting factor for the cultivation and popularization of A.albus seeds.Therefore,it is necessary to explore the dormancy characteristics and seed dormancy methods of A.albus seeds,and study the cultivation techniques of seedling,so as to provide guidance for the production practice of konjac seed.The main results are as follows:1.Biological investigation of natural pollinated A.albus and seedCollecting the natural pollination of A.albus plant in A.albus producing area,counted and measured the basic characters of plant and seed.Results showed that,peduncle length is 27.05 cm,length of fruit stalk is 2.88 cm,total fresh weight is 6.57 g,fruit number is 24,anthocarp rate is 18.93%,the bulbs of the fruit are all heavy 45.29 g.A round or oblong seed,vertical diameter 7.59 mm,diameter 5.73 mm,thickness 5.18mm.The weight and shape of strong character variation rate anthocarp,peduncle length,stalk length,total fresh weight,seed aspect and thickness are moderate variation.2.The dormancy cause of the seed of A.albus seedIn the seed water permeability test,the water absorption rate of the broken seed was 22.13%,which was 6.29%higher than that of the intact seed.It is clear that there is a pervious barrier in the coats of the A.albus.The bioassay of methanol and water extracts from seeds and pulp was carried out.The results showed both seed and fruit pulp contain inhibitory substances that inhibit seed germination and Seedling Growth3.Techniques for relieving dormancy of A.albus seedThe germination bed?A factor?was treated with different concentrations of gibberellin?B factor?for different time?C factor?.The results showed that the germination bed was river sand,and 50mg/L GA₃ was used to treat seed 24 h,and its germination rate increased to 80%.The effect of seed germination with different concentrations of NaOH,H₂O₂ and HCl solution was the effect of seed germination,the germination rate of seeds treated with 3%H₂O₂ could be increased to 60%and 52.54%after treatment with 1 h and 2 h.The germination rate of seeds treated with 10%HCl could be increased to 53.33%after treatment with 2 h.There were significant differences with the control.NaOH solution can not promote seed germination.The results of IAA and 6-BA solution treatment seeds showed that the germination rate of seeds treated 12h with IAA solution was higher than that of CK.Seeds treated 12 h with IAA solution and 6-BA solution for 12 h and 24 h could not increase seed germination rate.In the low temperature stratification,room temperature stratification,warm temperature stratification treatment results showed that the seed dormancy can be effectively relieved when room temperature stratification and warm temperature stratification treatment 60 d,of which,the germination rate of warm temperature stratification can reach more than 90%,and the effect was better..4.Study on water loss after postharvest seed of A.albus seedThe seeds of A.albus were dried at 25,35 and 45 degrees respectively.The results showed that the activity of POD and SOD decreased with the prolongation of treatment time.Pro content increased at all temperatures at 64h,while MDA decreased at first and then increased.The electrical conductivity increased significantly after 45 16h treatment,and the conductivity value was lower under other treatments.The seed viability of different temperature treatments was determined.When seeds were treated at 45?in32h,the vigor of seeds would be affected,while other treatments would not affect seed vigor.It is indicated that the seed can not exceed 16h at 45?,otherwise it will affect the vigor of the seed.Natural drying of the seeds treated with the extension of time,POD and SOD activity decreased,Pro content increased gradually,and the content of MDA decreased,the conductivity increased in dry 32 d,but did not affect the seed vigor.5.Effects of different stratification on Seed Dormancy and contents of A.albus seedThe contents of the seeds were measured during the low temperature stratification,room temperature stratification and warm temperature stratification.The results showed that the physiological and biochemical changes of seeds with different stratification treatments were basically the same.The content of soluble sugar increased with the prolongation of stratification time,and the starch content increased first and then droped,The protein content showed a"rise-drop-up"trend;the fat content also showed a"rise-drop-up"trend.The results showed that the life activity of Amorphophallus seeds was gradually strengthened and the consumption of nutrients increased gradually.Antioxidant activity of POD decreased first and then increased,PPO activity showed a"rise-drop-up"trend,SOD activity increased firstly and then decreased,CAT activity is more complex,but the whole was the trend of"rise-drop-rise".On the whole,the content of endogenous hormones changed,and the content of ABA first decreased and then increased,while the contents of IAA,GA₃ and ZT showed the trend of increasing at first and then decreasing,there was a"turning"point in the process of processing 60d.The ratios of IAA/ABA,GA₃/ABA and ZT/ABA increased at first and then decreased.In the late stage of stratification,the hormone ratios were all larger than those of the control,indicating that the dormancy of seeds was gradually broken with the prolongation of stratification time.6.Study on the cultivation technique of A.albus seedThe orthogonal experiment on the different sowing date,density and planting depth of A.albus was carried out,and the A.albus was used as the control.The results showed that in May 9th,the emergence rate and seedling rate of A.albus were higher than that of April 19th and 29th,while A.konjac planted at 9 cm depth,and the rate of multiple seedlings was higher in May 9th.In terms of leaf area,the leaf area of the second seedlings of 3 treatment and 7 treatment of 9 cm was the largest,indicating that the growth depth of A.albus grown at depths of 9 cm was better,and the leaf area value of A.konjac planted in April 19th was larger than that of the A.konjac.In the aspect of chlorophyll,the A.albus was larger in the treatment of 1,3,5 and 9,and the depth of cultivated konjac in April 19th was the largest of 9 cm.In terms of yield,the depth of 6and 9 cm of A.albus in April 19th was larger,followed by treatment 6 and treatment 7,while the yield of A.konjac was the largest in treatment 6.However,there was no significant difference in seedling rate,seedling number and chlorophyll leaf area between different planting densities.Therefore,The best planting time for A.albus and A.konjac area is in late April in Shizhu,and the depth of planting is also 9 cm.