Changes in the properties of rice varieties with different amylose content on dry heat parboiling

Dry heat parboiling is a unique paddy processing technique that has been scarcely exploited. Dry heat parboiling at high temperature for short time and low temperature for long time on physical and physicochemical properties of three rice varieties differing in amylose content were studied. Hardness of the kernels increased from 66.4 N, 68.8 N and 59.8 N in raw samples to 89.1 N, 86.9 N and 59.8 N in parboiled high amylose, low amylose and waxy rice samples respectively. Rapid migration and evaporation of water from severely heated kernels caused cavity formation at the centre. Irreversible damage of amylopectin structures to leachable fractions caused continuous rise of the pasting curve. Crystallinity was thereby reduced. Parboiled high amylose samples gave X-ray diffraction patterns with peaks characteristic of A, B and V-type starch crystallinity. Crystalline starch-lipid complexes were observed in low amylose and waxy rices. The significant increase in the amount of rapidly digestible starch from 56.7%, 61.7% and 66.6% in raw samples to 92.1%, 90.8% and 94.8% respectively in severely processed rice samples and subsequent reduction in resistant starch from 24.5%, 21.2% and 18.4% to 0.4%, 1.9% and 0.1% indicated possibilities for targeted food use of the dry heat parboiled samples.     

调环酸钙25%悬浮剂对直播稻抗倒伏和产量性状的影响

为了研究新型植物生长调节剂调环酸钙在直播稻上的应用效果,本研究设计了调环酸钙25%悬浮剂在直播稻武运粳8号上的田间试验,用来了解其对直播稻的抗倒伏性状和产量性状的影响。试验结果表明:在直播稻武运粳8号的分蘖期使用调环酸钙25%悬浮剂12~15g/667m2均能够显著降低水稻的株高,缩短茎基部节间长度,提高水稻的抗倒伏能力,同时也能显著提高水稻产量。     

水稻耐寒恢复系科恢36的选育与应用

科恢36是重庆师范大学以明恢63/泰引1号(9)//糯89-1(♂)杂交选育而成的水稻新恢复系,具有耐冷性强、恢复力强、花粉量充足等特点,2013年通过重庆市技术鉴定,所配组合冈优36(冈46A/科恢36)于2012年通过重庆市品种审定.     

中浙优8号在沙县作烟后稻种植表现及高产栽培技术

中浙优8号是中国水稻研究所和浙江勿忘农种业股份有限公司采用优质不育系中浙A与恢复系T-8配组而成的优质高产迟熟三系杂交稻新品种,经过3 a在沙县作烟后稻示范种植,表现群体整齐、分蘖力强、结实率高、米质较优、丰产稳产性好等特点。介绍其在沙县示范表现及高产栽培技术。     

沙柳木粉液化残渣的结构表征

以多元醇为液化剂(m(聚乙二醇)∶m(丙三醇)=4∶1),浓硫酸为催化剂,对沙柳木粉进行液化试验。将所得的液化产物多次清洗得到不溶液化残渣,应用FTIR、XRD和SEM对液化残渣的化学成分、微观形貌进行表征研究。结果表明:沙柳木粉液化反应分为木粉分解阶段和液化产物缩聚两个阶段;反应30 min后得到的残渣的红外光谱特征峰大致相同。XRD分析表明,残渣中含有大量的Si O2,木粉液化时非结晶区首先被破坏而降解,残渣的结晶度升高;反应后期结晶区发生降解,残渣结晶度略有下降。SEM图像表明,随着反应的进行,残渣由纤维状变为尺寸更小的连在一起的块状堆积物。     

丘陵红黄壤区施用399对“一种两收”再生稻根系和产量的影响

[目的]研究399对"一种两收"再生稻的影响。[方法]以适宜丘陵红黄壤种植的丰两优香1号、准两优527、宜优673再生稻品种为材料,分别设置喷施399和不喷施399(CK)2种处理,研究各处理对再生稻根系和产量的影响。[结果]结果表明:施用399使水稻在生育期上延缓成熟,且施后再生稻的总根系数量、白根数量、根鲜重、根干重、根体积大幅度增加,同时在两季总产量上准两优527、丰两优香1号和宜优673品种分别比对照增产6.39%、4.86%、5.94%。[结论]施用399有利于准两优527、丰两优香1号和宜优673再生稻品种再生根的发生。     

直剪法用于糙米内摩擦角的测定与研究

利用土工合成材料综合测定仪（直剪仪）,以水分含量14.57%的糙米为样品,测定了在不同的法向压应力、不同的剪切速率下糙米的剪切应力并计算出内摩擦角。实验结果表明：糙米的剪切应力随着法向压应力（25kPa～100kPa）的增大而增大;剪切速率（1.33mm/min～2.67mm/min）较低时糙米的内摩擦角随着法向压应力的增大而减小;随着剪切速率（1.33mm/min～5.20mm/min）的增大,糙米的内摩擦角减小。     

Evaluating the role of seed priming in improving drought tolerance of pigmented and non‐pigmented rice

This study was conducted to evaluate the influence of seed priming on drought tolerance of pigmented and non‐pigmented rice. Seeds of pigmented (cv. Heug Jinju Byeo) and non‐pigmented (cv. Anjoong) rice were soaked in water (hydropriming) or solution of CaCl₂ (osmopriming). Seeds were sown in soil‐filled pots retained at 70 (well‐watered) and 35% (drought) water‐holding capacity. Drought stress caused erratic and poor stand establishment and decreased the growth of both rice types. More decrease in plant height and leaf area under drought stress was noted in pigmented rice, whereas decrease in root length and seedling dry weight, under drought, was more obvious in non‐pigmented rice. Pigmented rice maintained more tissue water and photosynthesis and had more polyphenols, flavonoids and antioxidant activity than non‐pigmented rice. Seed priming was effective in improving stand establishment, growth, polyphenols, flavonoids and antioxidant activity; however, extent of improvement was more in pigmented rice under drought. In conclusion, drought caused erratic germination and suppressed plant growth in both rice types. However, pigmented rice had better drought tolerance owing to uniform emergence, and better physiological and morphological plasticity. Seed priming was quite helpful in improving the performance of both rice types under drought and well‐watered conditions.     

野生稻种质在水稻抗病育种上的研究及应用进展

野生稻是一个重要的基因资源库,包含了水稻各种病害的抗性基因。本文综述了野生稻丰富的抗性资源及其基因的挖掘,以及在水稻育种上的利用研究进展,并对目前存在的突出问题,提出了野生稻种质资源抗病育种的发展建议。