不同植物激素诱导砀山酥梨单性结实研究

以砀山酥梨为材料,通过不同浓度的GA4 7、GA3等植物激素及其不同浓度激素组合喷施花期未授粉的梨花朵,探讨不同植物激素诱导梨单性结实的效应。结果表明,单独施用GA4 7处理的坐果率与自然授粉的坐果率没有显著性差异,但比单独施用GA3或2,4-D NAA处理的坐果率高,并且能发育成与自然授粉相当大小的果实。花前对整个花蕾喷施GA4 7不能阻止其在花期完成授粉受精作用,喷施开放的花朵是诱导梨单性结实的有效方式。单性结实的梨果实果形变长,果形指数均大于1,显著地高于自然授粉果实（0.94）。除2,4-D NAA处理外,其它处理的果核直径显著地小于自然授粉的果实。单独喷施GA4 7诱导的果实可溶性固形物含量显著地高于自然授粉果实,其中GA4 7 75 mg L-1处理的可溶性固形物含量为14.10%,比自然授粉处理（11.40%）提高了2.7个百分点。     

生长调节剂对无核黄皮果实贮藏效果的影响

研究了6-苄基腺嘌呤（6-benzyladenine, 6-BA）、2,4-二氯丙氧乙酸（2,4-dichlorophenoxyacetic acid, 2,4-D）和赤霉素（gibberellin, GA3）处理对广东郁南无核黄皮常温贮藏效果的影响。结果表明,25℃贮藏10 d后, 6-BA (20 mg/L)、2,4-D (50 mg/L)和GA3 (100 mg/L)处理不同程度地提高了黄皮的好果率和可食率,延缓贮藏期间果实硬度、维生素C和蛋白质含量的下降,延缓可溶性固形物与可滴定酸含量的比值的上升。同时,3种处理不同程度地减少了贮藏期间果实的呼吸强度和乙烯释放量,减缓丙二醛（malondialdehyde, MDA）含量和电导率的增加。三种生长调节剂中,以6-BA处理的效果最显著。6-BA是适宜无核黄皮保鲜的生长调节剂,其通过延缓无核黄皮的成熟衰老进程,从而提高采后品质。     

木薯淀粉厌氧液对香蕉果实性状和品质的影响

本试验研究了木薯淀粉厌氧液(COD为800-1000 mg/L)直接定量施用到香蕉地上对香蕉果实性状和品质的影响。结果表明施用木薯淀粉厌氧液能显著改善香蕉果实的性状和品质,香蕉的果穗长度、果穗重、果梳数、每梳果指数、果指重、果指长度、果指围、果实的可溶性固形物含量、可溶性糖含量、可溶性蛋白含量、Vc含量均得到显著提高。     

幼果期喷施噻苯隆和赤霉素对芒果果实产量和品质的影响

本研究以海南‘贵妃’芒为材料,探究了幼果期喷施噻苯隆（ TDZ ）和 赤霉素（ GA3 ） 对果实品质的影响。结果表明幼果期喷施 TDZ 可显著增加产量和单果重,但果实品质略有下降,其中20 mg/L TDZ + 10 mg/L GA3 组合会降低‘贵妃’芒果可溶性固形物(TSS)含量和香气成分,但对果实颜色、总酸和VC含量影响不大,处理果实耐贮性增加,果实能够正常转色,果实香甜多汁,口感与对照果实相比差别不大。因此建议在幼果期喷施20 mg/L TDZ + 10 mg/L GA3 ,尽量降低植调剂过量使用对品质下降产生的影响。     

CPPU、TDZ对上海高桥地区夏黑葡萄果实生长与品质的影响

以上海高桥地区的夏黑葡萄为试验材料,盛花期和花后2周均使用50mg/L GA3处理,同时在花后2周分别添加0、1、3、5 mg/L CPPU和 TDZ,研究在花后2周添加TDZ和CPPU对夏黑葡萄果实生长发育及果实品质影响。结果表明：盛花期添加50 mg /L GA3,花后两周使用50 mg /L GA3 1 mg /L TDZ 处理的效果最好,增加了果实重量和可滴定酸含量,显著提高果皮花青苷含量,同时降低了可溶性固形物含量,而CPPU处理则会显著降低果实花青苷含量,不利于果实着色,导致成熟期推迟,这提示在实际生产中,应选用花后2周添加1mg/L TDZ作为上海高桥地区葡萄生产处理的参考。     

喷施GA3和2,4-D可减少留树贮藏脐橙落果

据《园艺学报》2012年第3期《喷施GA3和2,4-D对留树贮藏脐橙落果和内源激素含量的影响》(作者王雄等)报道,以纽荷尔脐橙为试材,测定喷施GA3和2,4-D的植株留树贮藏果实的落果率和果实内源赤霉素(GA)、生长素(IAA)、玉米素核苷(ZR)、脱落酸(ABA)含     

2,4-D、2甲4氯对沟叶结缕草草坪中天胡荽部分生理特性的影响

采用不同浓度的2,4-D与2甲4氯钠盐溶液分别对天胡荽进行了叶面喷施的杀灭处理,药后24h测定部分生理指标.结果表明2,4-D处理使天胡荽叶片叶绿素与可溶性糖含量降低,2000mg/L的2甲4氯钠盐溶液处理亦使其降低;2,4-D与2甲4氯钠盐溶液处理使叶片质膜相对透性增加,若浓度高于500mg/L,天胡荽叶片相对含水量、叶片可溶性蛋白含量均下降.     

壳聚糖对香蕉产量、品质及贮藏性的影响

壳聚糖能促进植株生长、改善品质及抗性。为了探讨壳聚糖对抗枯5号香蕉品种产量、品质及贮藏性能的影响,在香蕉生长过程中施用不同量的壳聚糖灌根 喷叶面。结果表明：与常规处理相比,施用壳聚糖能提高香蕉果指长度及果指重量,从而提高香蕉产量,壳聚糖10ml/株处理与常规处理差异显著,增产率为25.38%,利润率为47.66%;能显著增加果实可溶性固形物含量;能有效降低香蕉果皮花青素、类黄酮、总酚物质及丙二醛含量,降低果皮多酚氧化酶活性及果肉淀粉酶活性,增强香蕉果皮过氧化物酶活性和超氧化物酶活性,延缓香蕉果实衰老进程,提高果实的耐贮性。     

赤霉素和环割对灵武长枣生长发育、坐果及果实品质的影响

研究花期喷施不同浓度（10、20、30、40 mg/kg）赤霉素（GA3）和环割对灵武长枣生长发育、坐果及果实品质的影响。结果表明：GA3和环割提高1 a主枝叶片光合作用。 30 mg/kg的GA3处理显著促进1 a主枝枣吊伸长和加粗生长,环割处理枣吊长度和粗度与CK无显著性差异。20-40 mg/kg的GA3和环割能显著提高坐果率,但降低了果实横径、单果重。GA3和环割提高了灵武长枣果实Vc、可滴定酸含量,GA3降低了果实可溶性固形物、可溶性糖、糖酸比,环割处理可溶性固形物、可溶性糖、糖酸比与ck无显著性差异。结合主成分分析结果和坐果率情况,生产上喷施20 mg/kg的GA3,建议采用环割来调控树体生长。     

多效唑等几种药剂对柑桔的贮藏效应

2011-2013年在隆回县进行柑桔贮藏试验。结果表明,多效唑适宜作柑桔果实的杀菌防腐材料,但不适合作保鲜剂。采用1000mg/L多效唑与250mg/L 2,4-D或250mg/L防落素等保鲜剂混合浸果处理,可显著减少青绿霉、蒂腐病等引起的贮藏腐烂,防腐效果与1%食盐等杀菌剂相当,比单用显著提高。采前10天单用1000mg/L多效唑喷果,贮期在120天内可获得良好效果,生产上推广这项措施,采后可直接入库贮藏,不必进行浸果杀菌,可以节省大量时间,提高工效,同时还有利提高树体抗寒性。防落素用作柑桔保鲜剂,效果与2,4-D相当,完全可以取代2,4-D。     

补饲对牦牛生长发育影响的研究

(目的)为了充分挖掘牦牛生长发育潜力及补饲对其的影响,(方法)随机选择6月龄健康无病、体重相近的斯布牦牛20头分为试验组和对照组,每组公母各5头共计10头,在共同放牧条件下,试验组晚间自由采食草料精料比7:3混合饲料,对照组不予补饲,试验分3个阶段共计18个月(每6个月为一阶段)开展牦牛生长发育潜力挖掘研究。(结果)结果表明：第一阶段结束时,试验组牛的平均体重为79.20 kg,极显著的高于对照组牛的59.40 kg(P＜0.01);第二阶段结束时,试验组牛的平均体重为126.85 kg,极显著的高于对照组牛的99.53 kg(P＜0.01);第三阶段结束时,试验组牛的平均体重为155.05 kg,极显著的高于对照组犊牦牛的114.10 kg(P＜0.01)。整个试验期,试验组牛的体重较初始体重增加了101.10 kg,极显著的高于对照组牛的59.40 kg(P＜0.01)。(结论)说明通过放牧+补饲方式饲养6月龄牦牛至24月龄,较传统放牧条件下,牦牛18个月的总增重提高了70.20 %,效果极显著。     

Transforming growth factor β signaling in uterine development and function

Transforming growth factor β (TGFβ) superfamily is evolutionarily conserved and plays fundamental roles in cell growth and differentiation. Mounting evidence supports its important role in female reproduction and development. TGFBs1-3 are founding members of this growth factor family, however, the in vivo function of TGFβ signaling in the uterus remains poorly defined. By drawing on mouse and human studies as a main source, this review focuses on the recent progress on understanding TGFβ signaling in the uterus. The review also considers the involvement of dysregulated TGFβ signaling in pathological conditions that cause pregnancy loss and fertility problems in women.     

Regulatory role of l-proline in fetal pig growth and intestinal epithelial cell proliferation

l-proline (Pro) is a precursor of ornithine, which is converted into polyamines via ornithine decarboxylase (ODC). Polyamines plays a key role in the proliferation of intestinal epithelial cells. The study investigated the effect of Pro on polyamine metabolism and cell proliferation on porcine enterocytes in vivo and in vitro. Twenty-four Huanjiang mini-pigs were randomly assigned into 1 of 3 groups and fed a basal diet that contained 0.77% alanine (Ala, iso-nitrogenous control), 1% Pro or 1% Pro + 0.0167% α-difluoromethylornithine (DFMO) from d 15 to 70 of gestation. The fetal body weight and number of fetuses per litter were determined, and the small and large intestines were obtained on d 70 ± 1.78 of gestation. The in vitro study was performed in intestinal porcine epithelial (IPEC-J2) cells cultured in Dulbecco''s modified Eagle medium-high glucose (DMEM-H) containing 0 μmol/L Pro, 400 μmol/L Pro, or 400 μmol/L Pro + 10 mmol/L DFMO for 4 d. The results showed that maternal dietary supplementation with 1% Pro increased fetal weight; the protein and DNA concentrations of the fetal small intestine; and mRNA levels for potassium voltage-gated channel, shaker-related subfamily, member 1 (Kv1.1) in the fetal small and large intestines (P < 0.05). Supplementing Pro to either gilts or IPEC-J2 cells increased ODC protein abundances and polyamine concentrations in the fetal intestines and IPEC-J2 cells (P < 0.05). In comparison with the Pro group, the combined administration of Pro and DFMO reduced the expression of ODC protein and spermine concentration in the fetal intestine, as well as the concentrations of putrescine, spermidine and spermine in IPEC-J2 cells (P < 0.05). Meanwhile, the percentage of cells in the S-phase and the mRNA levels of proto-oncogenes c-fos and c-myc were increased in response to Pro supplementation, whereas depletion of cellular polyamines with DFMO increased tumor protein p53 (p53) mRNA levels (P < 0.05). Taken together, dietary supplementation with Pro improved fetal pig growth and intestinal epithelial cell proliferation via enhancing polyamine synthesis.     

Effects of delmadinone acetate on pituitary-adrenal function, glucose tolerance and growth hormone in male dogs

Objective To characterise the effects of delmadinone acetate on the pituitary-adrenal axis, glucose tolerance and growth hormone concentration in normal male dogs and dogs with benign prostatic hyperplasia.
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined.     

6个高丛蓝莓在贵州不同海拔生态区的生长发育表现

为探索高丛类蓝莓品种在贵州不同海拔生态区的栽培适应性,选择了莱克西、南大、绿宝石、密斯蒂、珠宝、蓝雨等6个品种,分别在海拔760m、1190m、1500m和1850m等4个生态区进行栽培试验。结果表明：莱克西、绿宝石、密斯蒂和蓝雨的树高随海拔高度的升高呈上升-下降的趋势,南大和珠宝则是不断下降,其中珠宝下降趋势最明显,除莱克西以外的5个品种的单株产量也呈显著降低趋势;随着海拔高度的上升,6个品种的新枝萌发力、长势由强变弱,初花期、盛花期、果实成熟期及果实采收期均延后,果实大小也逐渐由大变小。高海拔地区的可溶性固形物、Vc、可溶性蛋白质含量均高于中低海拔,可滴定酸含量则是先上升后下降。所有品种的总花青苷含量与海拔高度呈正相关,绿宝石、密斯蒂、珠宝和蓝雨的氨基酸含量也随海拔高度的升高而增加,其幅度分别为24.45-31.10mg/g、26.83-39.50mg/g、19.64-29.40mg/g、23.82-35.40mg/g。珠宝和蓝雨的挥发性物质含量随海拔高度增加而降低,分别为431.28-141.7μg/g和89.54-46.2μg/g,而南大和绿宝石则相反,为256.24-303.20μg/g和123.52-221.5μg/g。     

Excess dietary cholesterol may have an adverse effect on growth performance of early post-larval Litopenaeus vannamei

One experiment was conducted to determine the nutritive value of cholesterol for post-larval shrimp, Litopenaeus vannamei. Four isoenergetic and isonitrogenous diets supplemented with four levels of cholesterol (D1, D2, D3 and D4 with 0, 0.5%, 1% and 2% cholesterol, respectively) were fed to triplicate groups of L. vannamei shrimp (mean initial wet weight 0.8 mg) for 27 days. After the trial, shrimp fed the D1 diet had the best growth performance (final body weights: FBW; weight gain: WG; specific growth rate: SGR), while there was no significant difference between diet treatments with respect to survival. The whole body crude protein level in the shrimp decreased with the increase in dietary cholesterol levels, while the whole body crude lipid level in shrimps in the D4 diet treatment was significantly higher (P < 0.05) than in other diet treatments. Dietary analysis indicated that the D1 diet contained 0.92% cholesterol prior to supplementation, which may have satisfied the dietary cholesterol requirement of post-larval L. vannamei; excess dietary cholesterol may thus lead to adverse effects on the growth performance of post-larval shrimp.     

Deleting maternal Gtl2 leads to growth enhancement and decreased expression of stem cell markers in teratoma

The distal region of mouse chromosome 12 harbors the Dlk1–Dio3 domain, is essential for normal development and encodes maternally expressed noncoding RNAs (ncRNAs), including Gtl2 as well as paternally expressed proteins.Gtl2 works as a tumor suppressor in several types of human cancer cell lines; however, whether this reflects its function in vivo is unknown. Deleting Gtl2 from the maternal allele (Gtl2^(–/+)) results in loss of expression of Gtl2 and decreased expression of downstream ncRNAs, including many miRNAs. To determine the role of ncRNAs in tumorigenesis, we induced teratomas by engrafting E6.5 embryos (wildtype or Gtl2^(–/+)) under the kidney capsule of scid mice. Some teratomas derived from the Gtl2^(–/+) embryos exhibited hypertrophic growth, suggesting that ncRNAs, including Gtl2, may act as tumor suppressors in vivo. Microarray analysis of miRNAs expressed by Gtl2^(–/+) teratomas revealed decreased expression of 28 miRNAs encoded by the Dlk1–Dio3 domain, low expression of embryonic stem cell-specific miRNAs and dysregulation of miRNAs involved in tumorigenesis. This study suggests that downregulation of ncRNAs in the Dlk1-Dio3 domain leads to enhanced teratoma growth and repression of stem cell markers.