台农4号菠萝贮藏保鲜的研究

本文报道采用ＭＲ－０３保鲜剂处理的“台农４号”菠萝，置于常温（２５．２—２８．６℃）下贮藏２０天，好果率达９６．７％．贮藏３０天，好果率达７３．３％，系最高．经生理生化分析，ＭＲ－０３处理的果实在贮藏过程中，其呼吸强度和细胞膜渗透率均维持在较低水平，贮藏结束分别为１３．２４ｍｇＣＯ＿２·Ｋｇ￣（－１）ｈ￣（－１）和４８．９％，系最低．果实中总糖、总酸、可溶性固形物和Ｖｃ分别为１１．９％、０．５０％、１２．３％和６．０４ｍｇ／１００ｇ，与贮前相比，下降幅度最小．还原糖为７．１％，与贮前相比，增加幅度最大．同时，通过对果实的感官品评，其结果为：果实失水较少，果眼饱满，果皮鲜黄，果肉爽脆．甜酸适宜，且具有浓郁的菠萝香味．     

低温贮藏对‘松风本’龙眼果实品质和耐贮性的影响

本文以‘松风本’龙眼果实为试验材料,研究贮藏温度对龙眼果实贮藏品质和耐贮性的影响。采后龙眼果实经过挑选、清洗等预处理后晾干,用聚乙烯保鲜袋（0.015 mm厚）包装,分别置于室温(25±0.5)℃和低温(3±0.5)℃下贮藏。贮藏期间定期取样测定龙眼果实的营养品质和耐贮性指标。结果表明：与(25±0.5)℃室温贮藏相比,(3±0.5)℃低温贮藏可以有效延缓龙眼果实采后呼吸强度,保持较高的果皮色素（叶绿素、类胡萝卜素、花色素苷、类黄酮）含量和果肉营养物质（可溶性固形物、可溶性总糖、蔗糖、还原糖、维生素C）含量。此外,(3±0.5)℃低温贮藏还能延缓采后龙眼果肉自溶和果皮褐变,以及抑制龙眼果实失重率的升高,维持较高的龙眼果实商品率。据此认为,(3±0.5)℃可以作为‘松风本’龙眼果实低温贮运的推荐温度条件,以保持‘松风本’龙眼果实的贮藏品质和延长其保鲜期。     

常温下荔枝贮藏保鲜的研究

测定了不同保贮条件下荔枝褐变相关生理指标：多酚氧化酶（ＰＰＯ）、过氧化物酶（ＰＯＤ）、透性和呼吸强度的变化，同时，也测定了保贮期相应的营养成分：可溶性固形物、维生素Ｃ、类胡萝卜素、水溶性蛋白、游离氨基酸、糖等的变化。结果表明：乙烯吸收剂＋ＳＳＣ（１％ＮａＣｌ＋２％Ｎａ２Ｓｏ３＋５％柠檬酸的溶液）浸果贮藏，糯米糍品种荔枝在常温条件下，可延长贮藏７－１ｄ，保持色香味不变。     

‘福眼’和‘东壁’龙眼果实贮藏性与采后品质变化比较

比较研究了福建省主栽品种‘福眼’和‘东壁’龙眼果实在(8±1)℃、85％相对湿度条件下贮藏的果实贮藏性和品质变化差异.结果表明:与‘福眼’龙眼相比,‘东壁’龙眼果实贮藏性较好,采后贮藏期间的‘东壁’龙眼果实好果率较高,而果实失重率、果皮褐变指数、果肉自溶指数、果肉褐变度较低.采收当天的‘东壁’龙眼果实的果肉可溶性固形物(TSS)、总糖和维生素C含量都高于‘福眼’龙眼.采后贮藏期间,‘东壁’龙眼果实的果肉TSS、可滴定酸、维生素C和总糖含量的变化比‘福眼’龙眼果实少;在同一贮藏时间,‘东壁’龙眼果实的果肉TSS、维生素C和总糖含量都高于‘福眼’龙眼果实.因此认为,‘东壁’龙眼果实的贮藏性较好.     

缺镁对龙眼叶组织活性氧代谢及膜系统的影响

通过水培试验,研究缺镁对龙眼幼苗叶组织活性氧代谢及膜脂过氧化作用的影响。结果表明,随着缺镁症状加重,龙眼叶片细胞内Ｋ＋外渗量,ＭＤＡ含量、Ｏ２净产生速率和Ｈ２Ｏ２含量增加,活性氧清除系统的酶（ＳＯＤ、ＡＳＡ—ＰＯＤ、ＧＲ）活性提高。抗氧化物质（ＡｓＡ、ＧＳＨ）含量先升高,后下降。缺镁龙眼叶片抗氧化物含量和活性氧清除酶活性的提高是龙眼抵御活性氧伤害的一种适应性反应。缺镁龙眼活性氧伤害的原因可能与龙眼ＣＯ２同化能力下降,光合产物运转受阻有关。      

几丁质对贮藏期芒果几项生理指标的影响

研究了几丁质衍生物对贮藏期芒果呼吸强度，果实硬度、超氧物歧化酶（ＳＯＤ）活性和Ｖｃ含量的影响。结果表明，几丁质处理的芒果，贮藏到１５天时，其ＳＯＤ活力比未处理的高２２０单位，Ｖｃ含量高２７ｍｇＶｃ／１００ｇ，果实硬度高５．５ｋｇ／ｃｍ＾２，呼吸强度比处于呼吸高峰时的对照低。     

木薯渣固态发酵植酸酶的条件研究

木薯渣粗蛋白及无机盐含量较低,与麸皮、米糠混合或同时添加无机氮源及无机盐,可作为发酵培养基合成植酸酶。高浓度的磷抑制植酸酶的合成。最佳发酵条件为：木薯渣为唯一碳原,添加 ２％ ＮＨ４ＮＯ３, ０．０１％ Ｋ２ＨＰＯ４, ０．０５％ ＭｇＳＯ４·７Ｈ２Ｏ, ０．０５％ ＫＣＩ, ０．０１％ ＦｅＳ－Ｏ４· ７Ｈ２Ｏ, ０．９％ ＳＤＳ,培养基水分含量 ６０％～６５％, １０ｇ木薯渣／２５０ ｍＬ三角瓶,接种量为２ｍＬ菌悬液（２．８×１０个孢子／ｍＬ）,自然 ｐＨ值,培养温度 ２８～３１℃,第８ｄ达产酶高峰,高峰期产酶量为 ６７３０ Ｕ／ｇ干曲。      

S3307浸种对冬小麦生理特性及产量的影响

用不同浓度（１０、３０和６０ｍｇ／Ｌ）Ｓ３３０７浸种冬小麦。结果表明,冬小麦的比叶重,叶绿素含量、电解质渗出率,Ｏ２＾－产生速率,ＭＤＡ含量均低于对照,ＳＯＤ,可溶性糖含量高于对照,千粒重增加１．４２－２．０１ｇ,产量提高４．８％￣１２．１３％。从本实验的各项生理指标综合来看,Ｓ３３０７在冬小麦生产中具有一定的应用价值。     

采前喷施胺鲜酯对采后龙眼果实品质和耐贮性的影响

研究采前喷施胺鲜酯对采后龙眼果实品质和耐贮性的影响,为龙眼果实贮藏保鲜提供科学依据和生产指导。以‘福眼’龙眼为材料,在龙眼盛花期后70、90、110 d用浓度为10 mg/kg的胺鲜酯喷施龙眼果实3次,以蒸馏水喷施为对照。龙眼果实在盛花期后120 d采收,采后龙眼果实经过挑选、清洗和晾干后用0.015 mm厚的聚乙烯薄膜袋密封包装,在(28±1)℃、相对湿度85%下贮藏。贮藏期间取样测定果实呼吸强度、果皮色素含量、果肉营养物质含量和果实耐贮性指标。结果表明:与对照龙眼果实对比,采前喷施胺鲜酯可有效降低采后贮藏期间龙眼果实呼吸强度,保持较高的果皮叶绿素、类胡萝卜素、花色素苷和类黄酮含量,及较高的果肉TSS、可溶性总糖、蔗糖和维生素C含量,延缓果皮褐变和果肉自溶的发生,降低果实失重率,保持较高的好果率。因此认为,采前喷施浓度为10 mg/kg的胺鲜酯能有效延缓采后龙眼果实的品质下降、较好维持龙眼果实品质,提高龙眼果实耐贮性和保鲜效果。     

厌氧发酵法处理糖蜜酒精废水的研究

采用稀释和两段厌氧发酵工艺处理糖蜜酒精废水,试图消除硫酸盐还原产物Ｈ２Ｓ对厌氧微生物的影响,提高废水处理效率。结果表明,在３５℃条件下,发酵系统容积负荷率为５．３ｇＣＯＤ（Ｌ．ｄ）。容积产沼气率达２．０３Ｌ／（Ｌ．ｄ）,废不化学耗氧量（ＣＯＤ）去除率达６９．５％〈处理１ｍ＾３废水（ＣＯＤ值１０００００ｍｇ／Ｌ）可生产沼气３８ｍ＾３。     

马铃薯硫素吸收规律的初步研究

通过田间试验和室内测定分析,研究了马铃薯硫素吸收规律。结果表明:马铃薯全生育期内各器官含硫量始终以叶片最高,茎秆其次,块茎最低;全株硫的累积吸收量随生育进程的推进呈二次曲线变化,在淀粉积累期硫素累积量达到最大值;块茎形成至块茎增长期是马铃薯一生中硫素吸收速率最快、吸收数量最多的时期;生育期间硫素在马铃薯各器官的分配随着生长中心的转移,发生相应的变化,块茎增长期之前叶片中分配最多,其次为茎秆,块茎中最少,之后则是块茎中最多,茎秆其次,叶片中最少;硫在叶片中的分配率随生育进程逐渐降低,块茎中硫的分配率则为直线增长,茎秆中硫的分配率变化表现为单峰曲线,峰值出现在块茎形成期。本试验产量水平下,每生产500kg块茎需要吸收硫0.13kg。     

Relationship between total sulphur and sulphur amino acids in chickpea (Cicer arietinum L.) and pigeonpea (Cajanus cajan [L.] Millsp.)

Total sulphur was determined in seed meal of 30 chickpea and 24 pigeonpea cultivars by the wet digestion procedure and by using the Leco sulphur analyser. Methionine and cystine were determined after performic acid oxidation in an amino acid analyser. The two methods used for total sulphur determinations were highly correlated (r=0.943). Percent meal protein was significantly correlated (r=0.476) with total sulphur in chickpea but not in the case of pigeonpea. Total sulphur content exhibited a significant positive correlation (r=0.651) with sulphur amino acids of pigeonpea when expressed as percent of protein but not in the case of chickpea. Correlation coefficients between total sulphur and sulphur amino acids when the results were expressed as percent of sample were positive for both chickpea (r=0.494) and pigeonpea (r=0.534). The amount of sulphur in methionine and cystine accounted for 54.8% of the total sulphur in chickpea and for 75.5% in pigeonpea. In both chickpea and pigeonpea, methionine was positively and significantly correlated with cystine when they were expressed either as percent of sample or as percent of protein.Submitted as J.A. no. 159 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).     

施用硫磺粉对橡胶园土壤及周边水源影响初探

对海南两个不同地区使用硫磺粉防治白粉病后的农场胶园进行定位观测，分析区域内土壤和水中硫残留物的含量变化。结果显示，残留物的含量随着时间推移都呈现先增加、后减少的趋势，且与不同距离或不同作物的种植环境因素有关；此外，硫磺粉的施用对地表水和地下饮用水源产生一定的污染。最后提出使用硫磺粉防治白粉病需要科学用药、充分调研、统筹安排和研发新产品等建议。     

Sulphur concentration of soils and plants and its requirement for ruminants in the Inner Mongolia steppe of China

The sulphur status of four soils and 122 forage plants from the Inner Mongolia steppe was determined. The organic sulphur concentration ranged from 17 μg g^–1 in the 0·2–0·4 m soil layer to 397 μg g^–1 in the topsoil. The mean sulphate-S concentrations were <10 μg g^–1; greater concentrations were found only in the chernozem soil. Biomass-S accounted for 0·018–0·028 of total S in four soils. Three-quarters of plant samples examined had <1·6 g kg^–1 S, and >0·80 of them had an N:S ratio >14:1. More than 0·80 of the plants were deficient in S. There was a close relationship between plant-available soil sulphur concentrations and total plant sulphur concentrations. It was concluded that sulphur deficiency is widespread in the Inner Mongolia steppe and that sulphur fertilizer requirements should be evaluated.     

Effects of sulphur supply on the morphology of shoots and roots of alfalfa (Medicago sativa L.)

A sulphur (S)‐deficient top soil was used in a pot experiment to investigate the effect of S supply on shoot and root growth and development in alfalfa (Medicago sativa L.). The treatments consisted of three rates of addition of S: 0, 20 and 40 mg kg^?1 soil and each was replicated four times. Alfalfa was harvested at 15, 30, 45, 60 and 75 d after seedling emergence. By the end of the experiment, plants with S supply had a significantly larger leaf area, heavier leaf, shoot and root dry weight per pot than controls. The effects of adding S also significantly increased plant height, basal stem diameter, chlorophyll concentration of young leaves, root length and root surface area compared with controls. The effects of S were greater on shoots than on roots. The ratio of root to shoot dry weight was 0·47 when S was supplied and 0·88 without added S, indicating that c. 0·32 and 0·47 of the total net photosynthate, produced with or without S supply, respectively, were used for the development of roots. Overall, overcoming S deficiency resulted in a significant increase in shoot and root growth.     

Effect of supplementation with grain, hay or straw on the performance of weaner Merino sheep grazing old man (Atriplex nummularia) or river (Atriplex amnicola) saltbush

Old man saltbush ( Atriplex nummularia ) and river saltbush ( A. amnicola ) are widely used in commercial grazing systems on saline land in south-western Australia. Three hypotheses were tested during a 3-year study aimed at understanding the performance of weaner Merino sheep grazing saltbush-based pastures. The first hypothesis, that young Merino sheep grazing river saltbush would be better able to maintain live weight, body condition and would grow more wool than sheep grazing old man saltbush, was not supported by the data. Across the 3 years of the study, sheep grazing old man saltbush lost significantly less live weight and grew more wool (proportionately 0·06) than sheep grazing river saltbush. Differences in animal performance were considered to be associated with differences between the plant species in in vitro digestibility, concentrations of fibre, sulphur and crude protein in the herbage and the architecture of the Atriplex plants. The second and third hypotheses concerned supplementation strategies for sheep grazing saltbush. Three supplements were offered, namely barley grain, cereal straw or cereal hay, at a rate that approximated to one-third of the daily metabolizable energy requirements for maintenance of live weight. The performance of the sheep was higher when the grain supplement was offered but there was no effect of feeding roughage supplements compared to no supplementation. The findings suggested that the practice of feeding saltbush with adjacent crop stubbles is unlikely to be beneficial once any fallen grain has been consumed.     

常用封园药剂对茶橙瘿螨和假眼小绿叶蝉防治效果试验初报

在杭州茶区,通过45%晶体石硫合剂9、9%绿颖矿物油3、0%机油(石硫微乳剂为封园药剂,开展对茶橙瘿螨和假眼小绿叶蝉控害效果的试验,结果表明,三种封园药剂对茶橙瘿螨有较好的控害效果,对假眼小绿叶蝉控害效果则差异较大。     

马铃薯不同品种氮、磷、钾与硫素吸收规律的研究

以紫花白、夏波蒂、底西瑞为材料,采用田间试验与室内分析测定相结合的方法,对马铃薯不同品种氮、磷、钾、硫素的吸收、分配规律进行了系统的研究,结果表明:①在整个生育进程中马铃薯植株中氮、钾积累量表现为"M"型变化趋势,磷、硫积累量则表现为单峰曲线的变化趋势。②紫花白品种氮硫比随生育进程的推进呈"高-低-高-低"的变化趋势,底西瑞和夏波蒂品种的氮硫比随生育进程的推进呈波状变化,但两品种波峰和波谷出现的时期及次数均不同;紫花白和夏波蒂磷硫比的变化趋势相同,均为波状曲线变化,最大值分别出现在出苗后75d和95d,比值分别为4.60和4.09,底西瑞的磷硫比表现为"高-低-高-低"的变化趋势,出苗后95d时达到一生中的最大值6.34;3品种整个生育期间的钾硫比变化均表现出波状的变化趋势,波峰和波谷出现的次数和时期各不相同。③马铃薯氮、磷、钾素的积累与硫素积累之间存在着极显著的幂函数关系,即马铃薯氮、磷、钾素的积累量随硫素积累量的增加而呈幂函数增加。     

Determination of the Distribution of Sulphur in Wheat Starchy Endosperm Cells Using Secondary Ion Mass Spectroscopy (SIMS) Combined with Isotope Enhancement

Secondary ion mass spectrometry (SIMS) is a sensitive, high resolution technique capable of determining the location of elements or ions in a sample down to sub-cellular levels. The distribution of elements or ions are superimposed onto an image of the plant cell or tissue generated by ion-induced secondary electrons, allowing a visual representation of their positions in the sample. The elements are separated by their mass/charge ratios which can lead to a loss of sensitivity when separating signals from elements with very similar masses such as ¹⁶O₂ (31·990 a.m.u.) and³² S (31·972 a.m.u.). The abundance of ³⁴S isotope was, therefore enriched, allowing sulphur to be located at the starch granule/protein interface of the mature wheat grain. This demonstrates that isotopic enrichment can be used to extend the applications of SIMS technology to biological systems.     

Liveweight gains of lambs from Caucasian clover/ryegrass and white clover/ryegrass swards on soils of high and low fertility

The high nutritive value and persistence under a wide range of climatic and soil fertility conditions make Caucasian clover a potentially useful forage legume but there is little information about the performance of livestock grazing Caucasian clover/grass swards. This study compared liveweight gains of lambs grazing Caucasian clover/perennial ryegrass and white clover/perennial ryegrass swards on high fertility (Olsen P 20 mg L^?1, SO₄‐S 12 mg kg^?1) and low fertility (Olsen P 11 mg L^?1, SO₄‐S 7 mg kg^?1) soils from 1998 to 2001 in the South Island of New Zealand. Mean annual liveweight gains were 1178 kg ha^?1 for Caucasian clover/perennial ryegrass and 1069 kg ha^?1 for white clover/perennial ryegrass swards at high fertility compared with 1094 kg ha^?1 and 1015 kg ha^?1, respectively, at low fertility. There was a higher mean proportion of clover in Caucasian clover/perennial ryegrass (0·19) than white clover/perennial ryegrass (0·11) swards, but there were no differences in total herbage production between the two clover/perennial ryegrass swards. The mean concentration of crude protein in the herbage of Caucasian clover (302 g kg DM^?1) was higher than that in white clover (287 g kg DM^?1) and grass herbage (227 g kg DM^?1). Estimated mean metabolizable energy concentrations in the herbage were 12·5 MJ kg DM^?1 for the two clovers and 11·6 MJ kg DM^?1 for grass herbage. The difference in liveweight gain between swards on soils of high and low fertility was associated with an increase in total herbage production of similar composition and nutritive value, giving a greater number of grazing days for the swards on soils of high than low fertility.