不同添加剂处理对小麦秸黄贮饲料发酵品质的影响

为研究纤维素酶和乳酸菌制剂以及尿素对小麦秸黄贮饲料品质的影响,分别设不同的处理组及对照进行小麦秸黄贮饲料的发酵试验。实验Ⅰ结果表明:尿素单独添加、尿素和纤维素酶混合添加显著提高粗蛋白的含量,尿素和乳酸菌制剂、以及尿素与乳酸菌制剂和纤维素酶混合添加都不能得到品质较好的小麦秸黄贮饲料。实验Ⅱ结果表明:各添加剂处理均显著降低黄贮饲料的pH值和中性洗涤纤维含量(P<0.05),显著提高乳酸、总酸和粗蛋白含量(P<0.05);添加剂处理能够明显改善小麦秸黄贮饲料的发酵品质,提高小麦秸的饲用价值。纤维素酶和乳酸菌制剂同时添加时,小麦秸黄贮饲料品质最好。     

黑皮冬瓜品质综合评价方法的探讨

以24个不同来源、不同类型的黑皮冬瓜为试材,采用数据归一化法进行黑皮冬瓜品质综合评价体系研究。通过对可溶性固形物含量、总酸度、肉质致密性、含水量等营养品质性状以及皮色、瓜形等商品品质性状进行分析,结果表明：肉质致密性以及糖酸比等性状是衡量黑皮冬瓜品质优劣的主要指标,结合当前生产和消费的评价标准,制定了一套综合评价黑皮冬瓜品质的方法。     

脱落酸、水杨酸和草酸诱导苹果叶片脯氨酸积累的效应

 以3年生盆栽红富士(Malus domestica Borkh. ) /湖北海棠〔Malus hupehensis (Pamp) Rehd. 〕为试材, 研究了脱落酸、水杨酸和草酸预处理对叶片脯氨酸的诱导作用, 结果表明, 预处理第2天, 自然干旱效果还不明显时, 水杨酸预处理就使叶片脯氨酸含量提高了7.87%; 自然干旱、脱落酸、水杨酸和草酸预处理至第9天, 叶片脯氨酸含量较对照分别提高了96.30%、110.67%、135.12%和115.96%; 预处理9 d后停止供水至第5天时, 叶片瞬时水分利用效率分别提高了286.77%、75.76%、79.04%和100.44% ,脯氨酸含量也明显提高; 停止供水至第10天时, 脯氨酸含量分别提高了5.33%、262.76%、92.32%和0。综合比较显示, 自然干旱、脱落酸、水杨酸和草酸预处理都可以通过提高叶片脯氨酸含量和水分利用效率而增强苹果的抗旱性, 其中脱落酸的效果最好, 其次是水杨酸, 草酸效果持续时间比较短。     

Phenotypic characterisation of Phaeoacremonium and Phaeomoniella strains isolated from grapevines: enzyme production and virulence of extra-cellular filtrate on grapevine calluses

Extra-cellular enzyme production of different Phaeoacremonium spp. and Phaemoniella chlamydospora isolates were used to assay the possibility of inter-specific characterisation. Isolates of Phaeoacremonium aleophilum, Phaeoacremonium angustius, P. viticola and Ph. chlamydospora were grown on solid media and the activities of extra-cellular amylases, lipases, proteases, cellulases, xylanases, laccase, polygalacturonase, pectate lyase, lignin peroxidase, manganese peroxidase, urease and chitinase were assayed. Phaeoacremonium species showed activities of a larger number of enzymes and also enzyme activity was frequently higher suggesting that Phaeoacremonium can be more virulent. To assay if the produced extra-cellular enzymes could reflect the virulence capacity of the two genera, calluses of Vitis vinifera L. (cvs. Baga and Maria Gomes) and of a rootstock (R3309) were inoculated with filtrated culture liquid medium of three isolates of Ph. chlamydospora and one of P. angustius. Filtrates from all strains decreased callus growth and membrane integrity, while soluble protein content of calluses decreased with the strains CAP 054 and 1AS. P. angustius (CAP 054) induced the more severe symptoms in all genotypes. Water content decreased together with an increase of osmolality in both cultivars but not in rootstock suggesting that osmorregulatory capacity is more affected in cultivars. Data show that: (1) Phaeoacremonium and Phaeomoniella genera have different patterns of extra- cellular enzymatic production; (2) these fungi produce extra-cellular compound(s) that induce(s) senescence symptoms in plant cells inhibiting callus proliferation; (3) among the strains tested in plant calluses the most virulent isolate (CAP 054) also produced higher amounts of some extra-cellular enzymes; (5) rootstock calluses were less sensitive to inoculation than grapevine calluses.     

Hybridization and in vitro culture of an orchid hybrid Ascocenda ‘Kangla’

The present study focuses on hybridization program involving two species belonging to two different vandaceous genera, viz., Ascocentrum ampullaceum (Roxb.) Schltr. var. auranticum, a narrow endemic orchid of Manipur and Vanda coerulea Griff., an endangered orchid of Appendix I of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora), to synthesize the primary hybrid genus with intermediate and improved characters in the F₁ generation. Observations on the crossability in the present bigeneric cross between V. coerulea and A. auranticum had been achieved with 60% success when V. coerulea was taken as female parent. Murashige and Skoog (MS) basal medium at half-strength was effective for the development of the hybrid seedlings of V. coerulea × A. auranticum followed by Vacin and Went (VW) and Knudson C (KC) media. The best response of seedling growth was observed on MS medium at half-strength supplemented with 2.3 μM kinetin + 0.5 μM α-naphthalene acetic acid with maximum shoot height (2.7 cm), leaf number (4.6) and root number (4.1) after 150 days of inoculation. The survival percentage and growth performance of the seedlings were found to be higher (80% survival) in potting substrate consisting of brick:charcoal in the ratio 2:1 mulched with moss (Sphagnum sp.) than in potting substrate consisting of brick:charcoal:tree fern in the ratio 2:1:1. The first flowering was observed in the hybrid seedlings of V. coerulea × A. auranticum after 2 years of transfer to the ex vitro environment. Morphologically, the flowers differed from that of the parents clearly showing the success of the hybridization experiment. Registration of the hybrid has been made with the Royal Horticultural Society with the nomenclature Ascocenda ‘Kangla’ (No. T128725).     

苹果砧木SH40 和八棱海棠缺铁胁迫下根系有机酸分泌的差异

 以苹果砧木SH₄₀和八棱海棠(Malus micromalus) 的生根试管苗为试材, 采用水培方法, 研究了缺铁胁迫对根系分泌有机酸的种类和数量的影响。结果表明: SH40和八棱海棠根系分泌有机酸种类相同,主要是草酸、丙二酸、酒石酸、苹果酸和柠檬酸, 但在分泌总量上差异明显, 八棱海棠分泌有机酸总量大于SH₄₀。缺铁胁迫时SH₄₀草酸分泌量和八棱海棠柠檬酸分泌量大量增加, 且八棱海棠干物质和铁含量明显高于SH₄₀。草酸和柠檬酸分泌量增加可能是SH₄₀和八棱海棠耐受缺铁胁迫的原因之一。     

Cryopreservation of carnation (Dianthus caryophyllus L.) shoot tips by encapsulation-vitrification

Shoot tips excised from in vitro cultured plants of Dianthus caryophyllus L. (cv. Pallas, cv. Pink Candy and cv. Wanessa) were successfully cryopreserved using an encapsulation-vitrification method. Shoot tips (2–3 mm in length) were encapsulated in sodium alginate, precultured on liquid Murashige and Skoog (1962) medium supplemented with various sucrose concentrations (0.25, 0.5, 0.75, 1.0 M) for 24 h or 48 h and dehydrated with the vitrification solution PVS2 (up to 4 h) at 24 °C or 0 °C prior to direct immersion in liquid nitrogen (−196 °C). A maximum of shoot regeneration from cryopreserved shoot tips was obtained with the following combinations: preculture in 0.5 M sucrose and 180 min dehydration treatment at 0 °C for cv. Pallas (60% shoot formation), or preculture in 0.75 M and 200 min dehydration at the same temperature for cv. Pink Candy (66.6% shoot formation) and cv. Wanessa (73% shoot formation).     

Rooting response of shoot cuttings from three peach growth habits

Current year shoot cuttings were collected in October and August from three growth habits of peach (Compact, Pillar, and Standard) and treated with one of four concentrations of indole butyric acid (0, 250, 1250, and 2500 mg L⁻¹ IBA). Rooting response was measured after 5 weeks in the greenhouse. Little or no rooting occurred with cuttings from any growth habit that was collected in October or in August when treated with 0 and 2500 mg L⁻¹ IBA. In August, the number of shoots that rooted was greater in cuttings from Pillar (79 and 45%) than Compact (13 and 3%) treated with 250 and 1250 mg L⁻¹ IBA, respectively. Cuttings from Standard trees had intermediate rooting of 56 and 6% at 250 and 1250 mg L⁻¹ IBA, respectively. Pillar trees consistently grew more roots with greater root length per cutting than the other growth habits. It is proposed that differences in rooting response among the growth habits may be associated with differences in endogenous auxin concentration that had been found in previous studies. Within peach and possibly other fruit trees, the capacity of shoot cuttings to develop adventitious roots can vary by cultivar and successful root induction with exogenous plant growth regulators may depend, in part, on endogenous hormone levels.     

Effect of uric acid on the maturation and the biological function of BMDCs

AIM: To investigate the effect of uric acid on the maturation and the biological function of murine bone-marrow derived dendritic cells (BMDCs) in vitro.METHODS: BMDCs were cultured with GM-CSF, IL-4, LPS and uric acid. Cell phenotypes were analyzed by flow cytometry. MTT was used to detect the effect of uric acid on the function of BMDCs in stimulating the proliferation of T cells. IL-12 released by BMDCs was also detected. RESULTS: BMDCs were cultured and identified. Uric acid at concentrations of 200 mg/L and 400 mg/L increased the expression of the molecules (CD11c, CD83, CD86, IA/IE) on BMDCs surface and the IL-12 level in the culture supernatants (P<0.05), promoted the proliferation of T cells at the T: DC rate 5∶1, 10∶1, 20∶1 (P<0.05). However, uric acid at concentration of 70 mg/L had no effect on above molecule expression (P>0.05), no effect on T cell proliferation with BMDCs (P>0.05) was observed. CONCLUSION: Uric acid promotes the differentiation, maturation, the expression of co-stimulatory molecules, the IL-12 production in BMDCs and enhances the ability of BMDCs to stimulate the proliferation of T cell in a specical dose range.     

Improvements in somatic embryogenesis protocol in Feijoa (Acca sellowiana (Berg) Burret): Induction,conversion and synthetic seeds

Pineapple guava (Acca sellowiana) syn. Feijoa sellowiana, a Brazilian indigenous Myrtaceae is under domestication in South Brazil. Previous works showed that this species is responsive to somatic embryogenesis and recalcitrant to conventional methods of clonal propagation. In the present work it was evaluated the role of components of culture medium in the induction and development of somatic embryos. The technology of synthetic seeds was also evaluated. Zygotic embryos were inoculated in LPm medium supplemented with 8 mM glutamic acid and 8 mM l-glutamine, 2,4-dichlophenoxiacetic acid (20 μM) and myo-inositol. For conversion of somatic embryos and synthetic seeds it was tested the effect of 6-benzylaminopurine and gibberellic acid combined or not with activated charcoal. The highest values for embryogenetic induction (100%) and number of somatic embryos/explant (113) were observed in the LPm medium supplemented with Glu (8 mM), and 2,4-D. The culture medium supplemented with BA (0.5 μM) and GA₃ (1 μM) and activated charcoal (1.5 g L⁻¹) enhanced the conversion of somatic embryos to plantlets. Pre-germinated somatic embryos encapsulated in sodium alginate with BA (0.5 μM) and GA₃ (1 μM) developed radicles. The use of synthetic seed was a requisite for the survival of plantlets.