Effects of Sodium Chloride Stress on Growth of Sweet Potato Plantlets in vitro and Ion Content

[Objective] This study aimed to investigate the salt-tolerance mechanism of sweet potato.[Method]Two sweet potato varieties of Xu 25-2(salt-tolerant cultivar)and Triumph 100(salt-sensitive cultivar)were treated by sodium chloride with the concentration of 0 mmol/L and 100 mmol/L.After 20 days,Na+ content and Na+/K+ ratio in the roots,shoots and leave were determined by the flame photometer,while dry weight and fresh weight of roots,shoots and leave in different varieties were also studied.[Result]The growth of two sweet potato varieties was inhibited under salt stress,so the plant became shorter,leaf and root became fewer,dry weight of roots and leave decreased,but seedlings of Xu 25-2 were inhibited slightly.Furthermore,Na+ content and Na+/K+ ratio in roots,shoots and leaves of two sweet potato varieties increased.Na+ content of salt-tolerant Xu 25-2 was low in roots,shoots and leaves,while Na+ content of salt-sensitive Triumph 100 was high in shoots and leave of seedlings,but the change range of Xu 25-2 was less than that of Triumph 100.[Conclusion]The lower Na+ content and Na+/K+ ratio in leaves under salt stress were the most important characteristics for salt-tolerance of sweet potato varieties.

The Influence of Biochar on Growth of Lettuce and Potato

Pot experiments were conducted in a glasshouse to determine the growth pattern of lettuce, true potato seedlings （TPS） and single node cuttings of TPS in response to biochar. The treatments were arranged in a randomized complete block design with 5 treatments （0, 10, 30, 50 and 100 t ha^-1） ofbiochar from greenwaste with 5 replications in lettuce, 10 in TPS and 5 in single node cuttings of TPS. The observations recorded on growth parameters showed that biochar had significant effect on growth of lettuce but no consistent effect on growth of TPS and single node cuttings. Among the biochar rates, 30 t ha^-1 had the greatest influence on overall growth of lettuce. The pH and electrical conductivity increased as the biochar rates increased in all experiments. These results provide an avenue for soil management system by using biochar as an amendment in horticultural crops. However, their verification in the field is important for specific recommendations.

Effect of Pb and Cd Stress on the Growth of Potato and Its Antioxidase System

With the potato variety Xishu 1 as the test materials, this paper adopted tissue culture to study the effect of Pb and Cd stress with different mass fractions on potato growth and the antioxidase system. The results showed that under the stress of Pb （200 mg/kg） and Cd （20 mg/kg）, growth of potato had no obvious difference with that in control group; under the stress of Pb （ 〉200 mg/kg） and Cd （ 〉20 mg/kg）, potato growth suspended, and its physiological indexes such as dry weight, plant height, root number, root length were inhibited obviously. With the increasing mass fraction of Pb, relative electrical conductivity, MDA and proline of potato leaves showed the tendency of increase, and the results in high mass fraction treatments showed significant difference with those in the control group （P 〈 0.05 ）, CAT, POD and SOD activity of leaves increased greatly with the increasing mass fraction. In the Pb stress treatment （200 mg/kg）, relative electrical conductivity, MDA and proline of potato leaves showed no obvious difference with those in the control group, and the results in high mass fraction treatments were significantly higher than those in the control group （ P 〈 O. 05 ）, CAT and SOD activity increased greatly with the increasing mass fraction （ P 〈 0.05 ）. Under the stress of Pb and Cd, synthesis of soluble protein in potato leaves was strongly inhibited. The results showed that potato was tolerant to Pb and Cd of lower mass fraction, and damage of potato caused by Pb and Cd stress could be relieved by improving activity of antioxidase and reducing peroxidation of membrane lipid, and the tolerance reduced with the increase of stress.

The Effect of Plant Growth Regulator and Active Charcoal on the Development of Microtubers of Potatoes

With the detoxicated seedling of a potato cultivation breed named “Mire” as the material, the effect of auxins CCC, 6-BA, and active carbon to microtubers of potato (Solanum tubersum L.) was investigated under the in-vitro circumstances. The result indicated the exogenous auxins improved the production and quality of microtubers of potatoes. The effect of induction can be described as CCC > CCC + 6-BA > 6-BA > CK, the number of microtubers in per flask is 8.17 > 7.67 > 7.29 > 5.46, and the number of large potatoes in per flask is 6.33 > 5.17 > 3.17 > 1. In addition, by adding 0.5‰ of active charcoal, the growth period was shortened from 25.0 days to 9.33 days on average, and the amount of larger potatoes increased 8.54%. These results benefited the growth of microtubers of potato.

Establishment and Growth of Potato Micro-Cuttings in Sand Trays

Two separate experiments were conducted to evaluate the success of the establishment and growth of micro-cuttings of potato (5 - 6 cm tall) in sand trays [38 cm (L) × 28 cm (W) × 7.5 cm (H) plastic trays] under controlled environment (22?C ± 2?C, 60 - 75 μmosm–1?s–1 light energy for 16 h daily). In the first experiment, micro-cuttings of potato cv. Diamant were planted at six populations (500, 600, 700, 800, 900 and 1000 cuttings per tray) in treated sand (sun dry, 1% formaldehyde, 0.2% Dithane M-45 and control). The mortality percentage of micro-cuttings was nil for sun dry sand while formaldehyde and dithane M-45 treated sand had 1% - 4% against 15% in the control with the highest population density. Mortality of micro-cuttings in formaldehyde and dithane M-45 treated sand trays were found not to be related to pathogenic organism rather toxic effect of these two chemicals. Micro-cuttings in Sun dry and control treatments showed better growth performance than these in chemically treated sand trays. In the second experiment, urea @ 1, 2 and 3 g per tray was applied as solid form after 15 days of planting the micro-cuttings and as liquid form @ 0.5, 1 and 2% solution sprayed in the micro-cuttings repeatedly after 15, 30, 45 and 60 days of planting. The micro-cuttings which received urea as solid state died within 2 - 3 days and 2% urea solution was also detrimental. Urea solution @ 0.5% found to be very effective for vegetative growth of micro-cuttings in sand trays. The control was also good for vegetative growth but at a slower rate.

Influence of <i>Ocimum gratissium</i>Leaves Supplement on Growth Indices and Blood Constituents of Goats Fed Sweet Potato Peels with Cashew Nut Shell

The study was carried out to determine the influence of sweet potato peels and cashew nut shell supplemented with Ocimum gratissium leaves, using growth indices and blood constituents by goats. Eighteen goats with an average weight of 8.11 kg and aged between 8 and 9 months old were allotted to three dietary treatments with six animals per treatment in a complete randomized design. The compared diets which comprised combination of sweet potato peels and cashew nut shell with concentrate respectively were in different ratios which included diet I (30:25:45), diet II (25:30:45) and diet III (20:35:45). Each goat also received 8 grams of Ocimum gratissium leaves as supplement in the diet. The results showed that average feed intake (6.42 kg) and fed conversion ratio (2.15) were highest in diet I and significantly different from other diets. Diet II had the highest significant (P 3/L), lymphocytes (56.01%), monocytes (1.06%), total protein (7.65 g/dl), albumin (3.58 g/dl), globulin (4.07 g/dl) and triglyceride (2.29 mmol/L). White blood cell (7.01 × 103/L), neutrophils (49.82%), cholesterol (42.34 mmol/L), creatnine (1.59 mg/dl) and urea (18.29 mg/dl) were (P < 0.05) best in diet III, whereas initial bodyweight, average daily weight gain, eosinophils and basophils were not significantly different (P < 0.05). It is concluded that diet II has the potential to enhance growth rate and blood constituents of goats.

不同地膜的降解特征及其对旱区马铃薯生长和土壤微环境的影响

为筛选适宜宁南旱区马铃薯生长且对土壤环境友好的降解地膜类型,以不覆盖为对照,研究普通塑料膜、秸秆纤维地膜、生物降解膜的降解特征及其对马铃薯生长、土壤微环境的影响。结果表明,生物降解膜和秸秆纤维膜分别在播后90和60 d进入诱导期,生物降解膜和秸秆纤维膜均在播后150 d进入碎裂期;播后150 d的地膜质量损失率以秸秆纤维地膜最高,而普通塑料膜无明显变化。播后60 d,生物降解膜和秸秆纤维膜处理土壤蓄水量分别较对照显著提高21.4%和10.3%,而普通塑料膜处理与对照差异不显著。播后90~120 d,秸秆纤维膜和生物降解膜处理平均土壤温度分别较对照显著增加1.2和0.8℃。播后150 d,与对照相比,普通塑料膜和秸秆纤维膜处理土壤速效磷、速效钾含量提升效果显著。秸秆纤维膜处理细菌数量最高,而生物降解膜处理真菌和放线菌数量最高。播后150 d马铃薯地上部和地下部干物质累积量均以生物降解膜处理最高,马铃薯株高、茎粗和增产效果均以秸秆纤维膜处理最为显著。主成分分析结果表明,土壤细菌、放线菌数量是影响地膜降解的主要因素,而播后30~60 d土壤水分和播后60~120 d膜质量损失率对马铃薯产量形成至关重要。综上,秸秆纤维地膜降解效果优于普通塑料膜,且对改善旱地土壤微环境效果显著,可实现马铃薯增产,可代替普通地膜应用于旱作马铃薯生产中。本研究结果对筛选适宜宁南旱区农业可持续发展的最佳地膜类型具有一定的现实意义。

Adaptation of potato production to climate change by optimizing sowing date in the Loess Plateau of central Gansu, China

Potato grows in most part of China, it achieves higher yield and better quality in Gansu Province than in others. With global warming, its growth duration has been prolonged and sowing date become earlier than before. Therefore, to regulate its sowing date and growing period is of great significance for better harvest. In this study, experiments were conducted with six sowing-date treatments of potato in Dingxi, which is in the Loess Plateau of central Gansu Province in Northwest China in 2010. The growth period, morphological index and change in yield and their relationships with temperature, precipitation, and other climatic factors were investigated for each treatment. Results show that the crop with different sowing dates experienced different climate conditions, leading to distinct growth duration, plant height, and leaf area index. The growth duration was shortened due to a delay in sowing date. For each 15-day delay in sowing, the growth duration was reduced by 12 days on average. A significant linear relationship was found between numbers of days either from seeding to emergence or from flowering to harvest and mean temperature over the corresponding period. Dry matter accumulation, tuber fresh weight, and final yield were all decreased because of insufficient cumulative temperature over the shorter growing periods. Marked differences in tuber yield were discovered among the six treatments of sowing date, the potato planted on May 27 giving the highest yield. The potato planted either earlier or later would produce invariably lower yield than the treatment of May 27. Late May therefore can be taken as the optimum sowing time of potato in this region because the crop can fully utilize thermal resource. We conclude that to postpone sowing time is a good practice for potato production to adapt to climate warming in the Loess Plateau of central Gansu, China.

DBD等离子体与活化水对马铃薯生长特性及产量的影响

等离子体技术在农业生产、生物医学、环境保护等领域有着广泛的应用前景。论文采用多针-板电极制备等离子体活化水装置、板-板电极等离子体直接处理马铃薯装置,对比研究了不同放电功率下等离子体活化水、直接等离子体处理对马铃薯生长特性及产量的影响。2种装置均呈丝状放电,且放电功率与外施电压正相关;当最佳放电功率匹配时,等离子体活化水、直接等离子体处理均能显著改善马铃薯生长特性及产量。等离子体活化水的放电功率为53 W时,马铃薯植株高度、茎粗、鲜重、叶绿素质量分数及产量分别提升了6.4%、18.9%、25.9%、31.7%及17.5%;直接等离子体处理马铃薯的放电功率为8 W时,植株的各参数值增幅均在10%以上。研究结果表明:放电功率变化时,等离子体活化水的理化参数(pH值、氧化还原电位、电导率、过氧化氢、硝酸根离子、亚硝酸根离子)变化显著;随着放电功率的提升,直接等离子体处理的马铃薯吸水率先增长后下降,种皮刻蚀逐渐明显。论文的研究可为DBD等离子体与活化水在农业生产领域应用提供参考。

Generation of Virus Free Potato Plantlets through Meristem Culture and Their Field Evaluation

Different aspects of micropropagation through meristem culture for the production of virus indexed source plants, in vitro tuberization and field evaluation of the in vitro regenerated plants were studied on four commercial cultivars of potato (Solanum tuberosum L.) viz., Diamant, Cardinal, Shilbilati and Lalpakri. The investigation was conducted at Rajshahi, Bangladesh from December 2010 to March 2012 to produce virus-free potato plantlets through meristem culture, shoot multiplications with root induction as well as their acclimatization and evaluation of morphological characters and tuber yield under field condition. Shoot tips of 25 - 30 day old field-grown plants of above mentioned four cultivars were used for meristem isolation. After isolation, meristems of these varieties of potato were cultured on “M” shaped filter paper bridge in Murashige and Skoog (MS) liquid medium. Four different treatments of media formulations viz. 0.1 mg/L KIN + 0.1 mg/L GA3, 0.1 mg/L KIN + 0.5 mg/L GA3, 0.5 mg/L KIN + 0.1 mg/L GA3 and 0.5 mg/L KIN + 0.5 mg/L GA3 were used as plant growth regulators. From these formulations MS + 0.1 mg/L KIN + 0.5 mg/L GA3 was found to be the best for the primary establishment of meristem culture. The primarily established meristems were subcultured on to MS semisolid basal medium supplemented with four different treatment combinations of hormones viz. 0.5 mg/L BA + 1.0 mg/L IBA;0.1 mg/L KIN + 0.1 mg/L GA3;0.5 mg/L BA + 0.5 mg/L GA3 and 0.5 mg/L KIN + 0.5 mg/L GA3 were used to identify the suitable media compositions for shoot proliferation. Results showed that out of these four media treatments the formulation 0.5 mg/L BA + 0.5 mg/L GA3 was found to be the best suitable for shoot generation. Among the four cultivars of potato higher frequency of shoot proliferation (number of shoots/explant and longest shoot length) was observed in Diamant, though the highest shoot formation (76%) was recorded in Cardinal. Virus free in vitro grown potato plantlets were obtained through DAS-ELISA test and used substantially for micro-propagation. After gradual acclimatization of rooted plantlets of four potato cultivars, they were transferred into the field for cultivation and established successfully. It was observed from the field study of in vitro meristem-derived plantlets that there were no virus-affected plants. The virus-free exotic varieties were much superior in all vegetative attributes and yield compared to those of indigenous varieties with producing potato plants of normal height. In contrast, the indigenous varieties took a longer time to tuber initiation and maturity, lower plant height and number of leaves per plant, a higher number of tubers but a lower amount of tuber weight per plant, and poorer tuber grade than the exotic varieties. However, the variety Cardinal exposed the best performances in the context of survival percentage of plantlets (90%), days to tuber initiation (DTI), a number of leaves per plant (NL), tuber weight per plant (343.40%) and the percentage of rich tuber grade.

不同浓度烯效唑对鲜食甘薯生长特性及产量的影响

为了研究烯效唑对鲜食甘薯生长特性和产量的影响,以心香品种为试验材料,进行了4个不同浓度处理的对比试验。结果表明,喷施烯效唑所有处理的地上部与地下部鲜重比均低于对照,鲜薯产量和叶绿素相对含量均高于对照。说明喷施烯效唑能相对地延缓地上部生长,降低地上部能耗,提高光合效率,从而达到增产的目的。本试验中,以喷施75 mg·L^(-1)烯效唑处理效果最为理想,其667 m^(2)鲜薯产量为2528.46 kg,比对照增产13.35%,建议在生产中推广使用。

马铃薯蛋白饲料对断奶仔猪生长性能、免疫器官指数及抗氧化功能的影响

文章旨在探究马铃薯蛋白饲料对断奶仔猪生长性能、免疫器官指数及抗氧化功能的影响。试验将400头28日龄体重(7.93±0.14)kg的健康杂交仔猪随机分为4组,每个重复10头,各组分别饲喂添加0%、1%、2%和4%的马铃薯蛋白饲料的试验日粮。试验为期28d。结果表明:与对照组相比,补充2%和4%马铃薯蛋白组仔猪的平均日增重(ADG)分别显著降低9.87%和10.19%(P<0.05);补充2%和4%马铃薯蛋白组仔猪的F/G分别显著提高11.20%和11.11%(P<0.05);此外,补充0%~4%的马铃薯蛋白对仔猪初重(IBW)、末重(FBW)和平均日采食量(ADFI)均无显著影响(P>0.05)。补充2%和4%马铃薯蛋白组仔猪的淋巴结指数和胰腺指数显著低于对照组(P<0.05);与对照组相比,补充0%~4%的马铃薯蛋白组仔猪的脾脏指数显著提高(P<0.05);此外,补充0%~4%的马铃薯蛋白对仔猪肝脏、肾脂、腹股沟淋巴结和胸腺指数均无显著影响(P>0.05)。补充2%和4%马铃薯蛋白组仔猪血清SOD活性显著提高,且组间差异不显著(P>0.05);补充0%~4%马铃薯蛋白组仔猪血清OH显著降低(P<0.05);与对照组相比,补充2%~4%马铃薯蛋白组仔猪血清H_(2)O_(2)显著提高(P<0.05);此外,补充0%~4%马铃薯蛋白对仔猪血清过氧化氢酶(CAT)活性、总抗氧化能力(T-AOC)能力和一氧化氮(NO)含量均无显著影响(P>0.05)。总之,马铃薯蛋白添加量高于2%时,对仔猪生长性能有明显负面影响。因此,在本试验条件下,马铃薯蛋白最适添加量为1%。

‘藏农薯1号’不同级别种薯的病毒种类及生物学性状比较

种薯退化是制约马铃薯(Solanum tuberosum L.)产业发展的重要因素,不同级别种薯播种后在田间发病情况通常差异较大,进而影响其生物学性状及经济效益。以西藏自治区选育品种‘藏农薯1号’为试验材料,分析各级种薯(原原种、原种、一级种、二级种)在田间病毒再侵染情况,比较各级种薯植株生长发育、块茎品质和产量等生物学特性。原原种植株中仅检测到马铃薯S病毒,其他级别种薯植株中可检测到马铃薯卷叶病毒和S病毒。同时,原原种植株田间马铃薯卷叶病毒和S病毒病发病率和病情指数均较低,二级种则相反。在生长发育过程中,现蕾期叶片的叶绿素含量和光合速率最高;随着种薯级别降低,叶绿素含量和光合速率呈下降趋势,而株高差异小。不同级别种薯块茎淀粉和干物质含量差异小,还原糖含量随着种薯级别降低而降低。产量和商品薯率统计结果显示,原原种最高、二级种最低,而原种和一级种之间未见显著差异。考虑到种薯成本和经济效益,在‘藏农薯1号’马铃薯生产中,种薯应优先选用原种和一级种。

NaCl胁迫下外源亚精胺对马铃薯幼苗生理特征的影响

【目的】研究NaCl胁迫下外源亚精胺(Spd)对马铃薯幼苗生理特征的影响,为新疆盐渍化区域马铃薯种植提供技术参考。【方法】以晋薯16号马铃薯幼苗为材料,采用不同浓度NaCl模拟盐胁迫处理,研究外源亚精胺Spd对马铃薯植株生长、叶片抗氧化酶活性、渗透调节物质含量的影响。【结果】盐胁迫抑制了马铃薯植株生长,使得超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)等酶促类抗氧化酶活性表现为低盐胁迫促进,高盐胁迫抑制;抗坏血酸(ASA)、谷胱甘肽(DSH)等非酶促类抗氧化酶含量均降低;脯氨酸、可溶性糖、氨基酸含量升高;外源亚精胺(Spd)通过提高叶绿素含量、根系活力,调节渗透调节物质含量,增强抗氧化酶活性等方式维持植物体的正常生理代谢功能。【结论】外源亚精胺(Spd)可提升马铃薯耐盐性,缓解盐胁迫对马铃薯植株的抑制作用,其中0.9 mmol/L Spd(S 3)浓度缓解效果最明显。

Effects of Agro-Ecological Practices on the Productivity of Orange-Fleshed Sweet Potato (Ipomoea batatas (L.) Lam) and Soil Fertility in the Sudano-Sahelian Zone of Burkina Faso

This study consisted to evaluate the effects of ecological practices on the yield performance of the JEWEL of orange-fleshed sweet potato (Ipomoea batatas (L.) Lam). The study was conducted in a Sudano-Sahelian cropping system (Lantargou, eastern region of Burkina Faso). Agro-ecological practices consisted of the inputs of 3.20 t/ha of compost + 2.45 t/ha of wood ash (CO + WA);4.90 t/ha of wood ash (WA);6.40 t/ha of compost (CO) were compared to control with no inputs (T0). Each treatment was repeated four times. The crop management consisted of plowing, harrowing, raising of ridges with 40 cm height, burying of treatments, transplanting of cuttings, two weeding’s, and using of biopesticide called PIOL for crop protection. Composite soil samples per treatment were also collected at tuber harvest and analyzed to determine the effects of treatments on residual soil fertility. Results showed that the plant heights and diameters under the CO were significantly (P < 0.001) improved by 16% and 12% compared to T0. The WA treatment significantly increased the number of large tubers by 43% (P ≤ 0.01) compared to T0. Total tuber numbers, large tuber numbers and tuber yields of sweet potato under CO + WA were significantly (P < 0.001) and respectively improved by 27%, 50% and 31% compared to T0. All treatments increased soil organic matter, N, P and K contents, and reduced soil acidity compared with those obtained under T0. Soil K content was improved by 39% under CO + WA, and soil N content by 34% under WA compared to T0. Soil C/N ratio under CO + WA was reduced by 20% compared others treatments. But, the CO + WA treatment outperformed by improving residual soil N content by 38%, and the WA treatment by increasing soil K content by 50% compared to T0. In addition, soil pHH2O increased by 1.2 units under WA treatment compared to T0. As conclusion, the application of 6.4 t/ha of compost performed well to improve the vegetative growth of orange-fleshed sweet potato while the inputs of 3.2 t/ha of compost + 2.45 t/ha of wood ash were efficacy to significantly increase the tuber yields and improve the residual fertility of soil.

不同叶面肥对甘薯普薯32生长及产量的影响

以甘薯普薯32为试验材料,研究不同叶面肥对甘薯普薯32农艺性状、光合性状、产量和品质性状的影响,并对数据进行相关性分析和主成分综合评价。结果表明:不同叶面肥对普薯32的生长性状和光合性状影响不同,相关性分析表明产量与各性状呈正相关,其中产量与商品率和干物质率呈显著正相关;对不同叶面肥对普薯32的各性状进行主成分综合评价,希沃丰大量元素水溶肥和薯墩儿氨基酸水溶肥分别排名第1和第2,这两种叶面肥有利于甘薯普薯32生长,产量的提高和品质的提升,是适合普薯32的叶面肥。

0.3%氯化血红素可湿性粉剂对马铃薯生长与品质的调节效果

为了明确0.3%氯化血红素可湿性粉剂对马铃薯生长的调节效果,确定最佳用量,以克新6号马铃薯为材料,以8%甲哌鎓可湿性粉剂和清水分别作为药剂和空白对照,采取随机区组排列开展田间应用试验,分析不同用量0.3%氯化血红素可湿性粉剂配施专用助剂(SD)对马铃薯生长、产量及品质的影响。结果表明:处理1—处理5(667 m^(2)分别施用0.3%氯化血红素可湿性粉剂10、20、30、40、0 g,并配施SD 20 g)平均株高、全叶鲜质量、茎粗和小区平均产量均较空白对照有所增加,且均以处理4(667 m^(2)施用0.3%氯化血红素可湿性粉剂40 g+SD 20 g)最大,处理3(667 m^(2)施用0.3%氯化血红素可湿性粉剂30 g+SD 20 g)次之,2者小区平均产量较空白对照分别极显著增加13.80%、10.73%,但与药剂对照差异均不显著;处理1—处理5马铃薯块茎干物质量、淀粉含量、还原糖含量和VC含量等也均较空白对照有所增加,其中以处理4最高,处理3次之,2者均显著高于空白对照。安全性评价表明,各处理对马铃薯均是安全的。在马铃薯生产上,推荐每667 m^(2)使用0.3%氯化血红素可湿性粉剂30~40 g+SD 20 g。

不同生育期干旱胁迫对马铃薯生长特性、块茎产量和水分利用效率的影响

为了探究马铃薯对不同生育期干旱胁迫的响应,明确马铃薯各生育期的需水特性,本研究以马铃薯栽培品种华颂7号为试验材料,在大田遮雨棚下对马铃薯各生育期进行干旱胁迫处理,研究不同生育期干旱胁迫对马铃薯植株生长、干物质积累、块茎产量及水分利用效率的影响。结果表明,幼苗期干旱胁迫处理(T_(1))后恢复灌水,相较于对照,成熟期马铃薯株高、根长、干物质积累量和水分利用效率显著提高。在产量和产量构成方面,幼苗期干旱胁迫处理后恢复灌水,大薯率较对照显著提高11.00个百分点、小薯率较对照显著降低10.34个百分点,块茎产量较对照显著增加31.34%。块茎形成期和块茎膨大期干旱胁迫处理(T_(2)、T_(3))的块茎产量较CK显著下降58.41%和27.84%,T_(2)处理的大薯率较对照显著降低了25.34个百分点,但T_(3)处理的大薯率、中薯率、小薯率与对照相比无显著差异。相较于对照,淀粉积累期干旱胁迫处理(T_(4))对马铃薯单株干物质积累、块茎产量和产量构成影响不显著。因此,可对华颂7号在幼苗期进行适当干旱胁迫以提高块茎产量和水分利用效率,而在块茎形成期和块茎膨大期应保持充足的水分供应以确保块茎产量的形成,从而达到高产高效的目的。

发酵红薯渣对黄羽肉鸡生长性能、屠宰性能和肉品质的影响

本文旨在研究日粮添加不同水平发酵红薯渣对黄羽肉鸡生长性能、屠宰性能和肉品质的影响。先应用强迫饲喂代谢试验测定黄羽肉鸡对红薯渣发酵饲料营养物质的表观代谢率。再选用360羽1日龄黄羽肉鸡随机分为Ⅰ、Ⅱ、Ⅲ和Ⅳ4个处理组,每组6个重复,每重复15羽。对照组(Ⅰ组)饲喂基础日粮,试验Ⅱ组、Ⅲ组、Ⅳ组1~21日龄分别饲喂基础日粮+10、30和50 g·kg^(-1)的发酵干红薯渣(等量代替玉米),22~42、43~70日龄分别饲喂基础日粮+50、80和100 g·kg^(-1)的发酵干红薯渣(等量替代玉米),试验期为70 d。结果显示:黄羽肉鸡对发酵红薯渣营养物质粗蛋白质、粗脂肪、粗灰分、粗纤维和总能的表观代谢率分别为63.67%、65.72%、70.85%、72.45%和87.93%;日粮中添加发酵干红薯渣等量替代玉米对黄羽肉鸡的平均日增重、平均日采食量和料重比的影响不显著(P>0.05);与对照组相比,Ⅱ、Ⅲ和Ⅳ组胸肌和腿肌的pH值及红度(a^(*))值提高(P>0.05),滴水损失率和剪切力降低(P>0.05),蒸煮损失率显著降低(P<0.05)。在日粮中添加50~100 g·kg^(-1)发酵干红薯渣等量替代玉米可改善黄羽肉鸡肌肉品质。

枸溶性钾肥与水溶性钾肥等比例基施提高甘薯生育期钾素积累和产量

【目的】施钾可促进甘薯增产,探究枸溶性钾肥(硅钾肥)与水溶性钾肥(硫酸钾)不同比例配施对甘薯钾素积累和产量的影响,为提高甘薯钾肥利用效率提供依据。【方法】田间试验在河南汝阳进行,供试土壤为褐土,甘薯品种为‘普薯32号’,枸溶性钾肥为硅钾肥(含K_(2)O 25%、SiO_(2)15%、CaO 14%),水溶性钾肥为硫酸钾(K_(2)O 52%)。在施钾量为K_(2)O 150 kg/hm2,钾肥全部基施条件下,设置5个水溶性钾肥与枸溶性钾肥配施比例处理:100%∶0%(T1)、75%∶25%(T2)、50%∶50%(T3)、25%∶75%(T4)、0%∶100%(T5),同时设不施钾肥对照(CK)。在甘薯移栽后30、60、90、120天,取样测定甘薯茎长、生物量、钾素含量和产量,计算钾肥利用率。【结果】与CK相比,施钾处理显著提高了甘薯茎长、茎粗和生物量、块茎产量。移栽30天,甘薯茎长、茎粗和生物量大多以T1处理最高,T2~T5处理间差异多不显著;移栽后60、90、120天,甘薯茎长、茎粗和生物量均以T3处理最高,且T3处理显著高于T1和T5处理。施钾处理均显著提高了甘薯块根产量,以T3处理甘薯块根产量最高,较CK处理增加68.02%。与T1处理相比,T2、T3、T4处理提高了各时期甘薯的钾素吸收量,提高甘薯移栽后90、120天各部位钾含量,以T3处理的甘薯钾素积累量、钾肥偏生产力、钾肥农学利用率和钾肥表观利用率最高,显著高于T1处理。【结论】在相同施钾量和施用方法下,50%枸溶性钾肥和50%水溶性钾肥配施可更好地满足甘薯全生育期对钾素的需求,较全部施用水溶性钾肥可更有效地提高甘薯的钾素积累量、产量和钾肥利用效率。