几种抑制木薯采后生理性变质发生方法的比较

比较了热激、酸化和隔绝氧气3种处理对木薯采后生理性变质的影响，结果显示，热激和酸化都能在一定程度上延缓木薯PPD的发生，隔绝氧气是最为理想的抑制木薯PPD发生的方法。因此，通过过量表达或者干扰某些基因表达，降低以至于去除伤口处的氧气的方法将是防治木薯采后生理性变质的有效途径。     

估测木薯茎叶生物量的一数学模型

为构建木薯茎叶生物量的估测模型,调查了木薯上、中、下部的茎粗、株高、叶柄长等形态学指标与茎叶生物量的关系.结果表明,木薯茎叶生物量主要受下部茎粗和株高的综合影响,并且下部茎粗、株高与茎叶生物量的关系均为乘幂函数关系.通过模型拟合和择优得到木薯茎叶生物量的估测模型W=0.032 83d2.48 6h0.1824.经新的实测数据检验,理论值与实测值的相对误差率为4.46%,完全满足测量精度要求.     

木薯生氰糖苷研究进展

木薯是世界上第五大粮食作物。但由于含有生氰糖苷，食用处理不完全的木薯产品会对人体产生危害，这在某种程度上限制了其在食品中的广泛应用。因此，对木薯生氰糖苷的研究具有重要的现实意义。本文对木薯生氰糖苷的生物合成以及人们在降低生氰糖苷含量方面的研究工作进行阐述，并对未来获得没有或低含量生氰糖苷的木薯产品提出展望。     

木薯全粉的功能特性

开发推广木薯源大宗食物,充分发挥木薯的资源优势,拓展人们日常消费的食物资源,积极应对日益严重的粮食危机.通过对木薯全粉与鲜木薯、木薯淀粉中的营养成分的测定对比,及对木薯全粉的黏度特性、透光率、膨胀度等进行分析,并对木薯全粉的营养成分保留及功能性质进行评价,探讨木薯全粉在食品工业中的潜在应用范围.结果表明,木薯全粉相对于鲜木薯、木薯淀粉营养成分保持良好,食用安全,同时具有较好的加工性能,在食品工业中应用前景广阔.     

Root distribution ofDactyladenia (Acioa) barteri andSenna (Cassia) siamea in alley cropping on Ultisol. I. Implication for field experimentation

Root observations were carried out on a typic Paleudult in the humid forest zone of south eastern Nigeria in an alley cropping trial usingDactyladenia (Acioa) barteri andSenna (Cassia) siamea as hedgerow trees and the interrow space planted to maize/cassava intercrop. Rooting depth ofD. barteri andS. siamea exceeded 1.6 m. Lateral root propagation ofS. siamea was 15 m, and ofD. barteri was 5 m from the hedgerows. The whole no-tree control plot was within the range of roots of the adjacent hedgerows. Rooting density and depth ofS. siamea in the no-tree control plot was generally higher than of cassava.S. siamea and cassava root density were inversely correlated. Assuming radial symmetry of root propagation, water and nutrients were available from an area 6.1 and 2.3 times larger than the allocated plot size ofS. siamea andD. barteri, respectively. Data obtained in alley cropping trials, not considering lateral root propagation, can be invalidated through exploitation of the no-tree control treatment and nutrient acquisition by hedgerow species from a larger area than allocated, thus underestimating and overestimating the performances of the respective treatments. Possible alternative measures for avoiding root interference are discussed but no good solution can be given.     

Study on Feed Value of Cassava Residue for Growing-Fishing Pigs

To determine the apparent digestibility of cassava residue (CR) nutrient and the effects of CR on growth performance when replaced the different levels corn in diet,two experiments were designed.In the first experiment,8 Duroc×Landrace×Yorkshire crossbred barrow pigs with the similar weight (22.46 kg±1.08 kg) were chosen for determining the apparent digestibility of CR.The pre-test period lasted for 10 days,and the trial period lasted for 5 days.In the second experiment,160 Duroc×Landrace×Yorkshire crossbred pigs with the similar weight(21.09 kg±0.72 kg) were randomly divided into five groups with four replicates per group and eight pigs per replicate.The control group was fed with basal diet while the experimental groups were fed diets containing 5%,10%,15% and 20% levels of substitution of corn by CR,respectively.The pre-test period lasted for 5 days,and the trial period lasted for 30 days.The results showed that the content of CP and EE in CR were 2.73% and 0.68%,but CF and total energy were 15.34% and 13.55 MJ/kg.The content of Lys and Thr were 0.11% and 0.08%,respectively.Calcium and phosphorus apparent digestibility were low,just only 40.24% and 34.76%,respectively,while apparent total energy digestibility was 65.62%.The apparent digestibility of Arg,Glu,Tyr,Met,Leu and Val were higher than 80%.The average daily gain was reduced with increasing dose of CR,which the group of 15% and 20% addition were significantly lower than that of control group (P< 0.05).However,the average daily gain of 5% and 10% groups were no significant difference with the control group(P >0.05).The feed cost of 5% and 10% addition groups were decreased by 0.01 and 0.05 yuan.In conclusion,under this experimental condition,the appropriate addition of CR for growing-fishing pig (20 to 50 kg ) was 5% to 10% in the diet.     

木薯农艺性状及品质对不同海拔梯度的响应

为了探究木薯农艺性状及块根品质对不同海拔梯度的响应,进而明确海拔梯度变化对木薯生长的影响。以木薯品种‘SC205’、‘GR4’为材料,于800~1600 m的海拔上种植。同海拔木薯的株高、茎粗、主茎高和落叶高度随时间不断增加而增加,但同时间段,随海拔升高呈降低趋势,2个品种在8—10月生长最快,11月生长相对缓慢,到12月生长基本停止;随海拔梯度升高,同一木薯品种块根品质呈上升趋势,除粗纤维含量外,其他均差异达极显著;同海拔不同木薯品种间,除粗纤维含量外差异显著;块根品质含量最高多出现在海拔1400 m,最低在海拔1000 m或800 m。不同海拔下,海拔800 m、1000 m木薯生长旺盛,海拔1400 m块根品质相对较好,生产上应根据用途选择适宜的木薯种植海拔。     

纯木薯废弃物栽培平菇的配方优化及效益分析

【目的】筛选以纯木薯废弃物为原料、适合平菇栽培的培养基配方,为实现木薯产业废弃物资源化提供参考依据。【方法】以不同比例的木薯杆、木薯酒精渣配制成6个培养基配方,以桑枝屑、棉籽壳各半添加15.0%麸皮的常规配方作对照,通过袋栽方式栽培平菇,比较木薯杆、木薯酒精渣不同添加比例对平菇菌丝生长、生物学转化率及生产效益的影响。【结果】木薯杆、木薯酒精渣不同配比培养基对平菇菌丝生长及生物学效率的影响不同,综合考虑平菇菌丝生长、生物转化率及生产效益,以木薯杆52.00%-67.00%、木薯酒精渣30.00%-45.00%、石灰2.00%、石膏1.00%为配方进行平菇栽培效果较佳。【结论】以木薯杆、木薯酒精渣等纯木薯产业废弃物为原料并添加石灰、石膏的配方栽培平菇,既能有效利用木薯产业副产品,保护环境,又能保证生产平菇的经济效益。     

木薯二倍体及其同源四倍体叶片形态、生理及抗螨特征比较

为比较二倍体及其同源四倍体木薯叶片之间的差异,本试验以木薯华南205、南植199的二倍体及其同源四倍体植株为材料,测定其叶片形态结构和逆境生理指标,鉴定其抗螨性,并进行相关性分析。叶片形态结构和生理指标测定结果表明,木薯同源四倍体的叶片厚度、中裂叶宽、栅栏组织厚度、海绵组织厚度、栅海比、下表皮厚度、下角质层厚度、单宁含量、多酚氧化酶以及苯丙氨酸解氨酶活性均高于其二倍体,中裂叶长、叶形指数、气孔密度和丙二醛含量均低于其二倍体。抗螨性鉴定结果发现,木薯同源四倍体的抗螨性均强于其二倍体。相关性分析结果表明,螨害指数与叶片厚度、栅栏组织厚度、海绵组织厚度、下表皮厚度、下角质层厚度、多酚氧化酶活性以及苯丙氨酸解氨酶活性呈极显著负相关,与单宁含量呈显著负相关,与气孔密度、丙二醛含量呈显著正相关。本研究为木薯倍性育种、抗性育种工作提供了科学依据。     

基于生氰糖苷降解途径基因表达特性的木薯品种对二斑叶螨的抗性机制初探

为初步探究生氰糖苷降解途径2个基因α-HNL和β-glu在木薯品种对二斑叶螨抗性中的作用,本研究以抗螨木薯品种‘C1115’‘缅甸’‘SC9’和感螨木薯品种‘SC205’‘面包’‘BRA900’为材料,分析木薯生氰糖苷降解途径基因及其编码的生化酶在二斑叶螨取食木薯品种不同部位叶片（上部、中部和下部）不同时间后（1、4 d）的表达量及酶活性的变化情况。结果表明,α-HNL在感螨木薯品种上部和中部叶片中的表达量随螨害时间的延长而显著降低;在抗螨木薯品种的不同部位叶片中,α-HNL的表达量均随螨害时间的延长而显著升高,并且以中部和下部叶片的升高趋势更为显著。β-glu在抗、感螨木薯品种不同部位叶片中的表达量均很低,难以比较该基因的表达量在不同木薯品种、不同部位叶片受螨害后的变化情况,但在能检测到的少量样品当中,抗螨木薯品种的占比也多于感螨木薯品种。进一步进行酶活性分析结果表明,抗螨木薯品种受螨害后,随着时间的延长,降解途径基因α-HNL编码的α-HNL酶活性呈逐渐升高或维持不变的趋势,并且以中部和下部叶片的升高趋势更为显著,而在感螨木薯品种中,随着螨害时间的延长,α-HNL酶活性则呈逐渐降低或先升高后降低的趋势;β-glu基因编码的β-GLU酶活性在不同木薯品种中均呈较低的水平,这可能与其对应编码的基因表达量低有关,但总体而言,降解途径2个基因编码的降解酶α-HNL和β-GLU在抗螨木薯不同叶片组织中的活性总体上也显著高于感螨木薯。本研究初步揭示了不同木薯品种受螨害不同时间后,生氰糖苷降解基因和酶可能与木薯对二斑叶螨的抗性有关。