烟秆生物质炭基肥施用对烤烟产质量的影响

为探讨烟秆生物质炭基肥施用对烤烟产质量及病害发生的影响,以烤烟品种‘红花大金元’、‘K326’、‘云烟87’为研究对象,设置1个常规施肥处理(CK)和3个烟秆生物质炭基肥不同施用量处理(T₁为400 g/株,T₂为500 g/株,T₃为600 g/株),测定不同品种及处理下的烤烟生育期、农艺性状、发病率、经济性状、化学成分。结果表明：(1)与对照处理相比,施入烟秆生物质炭基肥均能延长烤烟‘红花大金元’、‘K326’、‘云烟87’的各生育期,且能显著提高烤烟的株高、茎围、有效叶片数、最大叶长和叶宽,其中‘红花大金元’的施用量为600 g/株、‘K326’和‘云烟87’的施用量为500 g/株时对烟株生长发育促进效果最佳。(2)施用烟秆生物质炭基肥处理的烟草花叶病、野火病和气候性斑点病发病率显著低于对照处理,其中‘红花大金元’和‘K326’的施用量为600 g/株、‘云烟87’的施用量为500 g/株时烟株病害发生率最低。(3)施用烟秆生物质炭基肥处理的烟草产量、均价、中上等烟比例和产值显著高于对照处理,其中‘红花大金元’的...     

烤烟新品种遵烟6号产量与农艺性状比较分析

遵烟6号是从烤烟品种红花大金元自然变异株中系统选育而成的烤烟新品种。以烤烟品种遵烟6号、红花大金元、K326进行大区对比试验,试验结果表明：遵烟6号的农艺性状表现较好,抗病性表现最佳,平均产量2 678.4kg/hm2,产值40 756.35元/hm2,均价15.22元/kg,上等烟率为51.12%,中等烟率为33.76%,均高于红花大金元和K326;初烤烟叶化学成分协调,感官评吸质量与K326相当。     

烤烟新品种遵烟6号的特性研究

遵烟6号是贵州省遵义市遵义县从红花大金元品种中获得的自然变异株,经多年系统选育而成,该品种叶片形态特征与红花大金元相似,遗传性状稳定,在株高、叶数、茎围、节距等主要农艺性状上有明显差异;经贵州省烟草科学研究所抗性鉴定和田间多点试验结果表明,遵烟6号中抗青枯病,感烟草花叶病,抗气候性斑点病的能力优于对照;主要经济性状产量、产值和均价均优于对照;各项化学成分指标均在优质烟叶适宜范围内,主要化学成分协调;初烤烟叶感官质量评吸与对照K326相当。     

烤烟新品种南江3号的特征特性研究

贵州省是种烟历史长、种烟面积广、品种更迭较快的烤烟大省,独特的海拔立体气候为外引品种变异提供了良好条件。南江3号就是贵州省贵阳市开阳县在红花大金元品种中发现的自然变异株,该品种农艺性状叶片形态特性与红花大金元相似,遗传性状稳定,田间生长整齐一致,在株高、叶片数、叶色、烟叶烘烤特性等性状上与原品种红花大金元有明显差异,单株有效叶数较多,叶片较大,叶色浓绿,生长势较强,叶片分层落黄,易烘烤;经贵州省烟草科学研究所抗性鉴定和多年田间自然发病调查结果表明,该品种中抗黑胫病和青枯病,感烟草花叶病,气候斑点病轻,抗叶斑类病害的能力优于对照;主要经济性状产量、产值和上等烟率显著高于对照;初烤烟叶外观质量总体略好于对照,主要化学成分含量适宜;比例较协调;感官品质与对照K 326相当。     

烤烟气候性斑点病与植株和土壤的营养关系

摘 要:本文针对在玉溪市烤烟生产上常发生的烤烟气候性斑点病问题,从发生原因的内部因素（烟株营养）方面,采用田间调查、采集配对样品与室内检测分析相结合的方法,并以根际土壤及植株各部位叶片等为探索对象,从病害在田间分布及叶片养分变化等方面开展了研究。结果表明,在烤烟初花期气候性斑点病发生叶位以第4－7叶位（由下至上）的叶片发生较多（占83.5%）。发生气候性斑点病的烟株,内因是由于植株N、Ca、Mg含量过高,而K含量不足,从而提高了 N/K、Mg/K及Ca/K比值,导致N、K、Ca、Mg营养不平衡,其根本原因是由于土壤有效N（特别是速效的NO3－N与NH4－N）及交换性Ca、Mg含量过高,有效K含量过低所致。关键词：烤烟;气候性斑点病;土壤养分;烟叶营养     

盘县烤烟特色品种筛选

烟叶是卷烟工业的原料,在很大程度上决定着卷烟的质量和风格。卷烟是一种嗜好品,不同类群的消费者对卷烟的风格具有不同的要求。本研究是在盘县烟区的特定生态背景下,以云烟87作为对照,筛选出适应盘县烟区的有特色的烤烟品种3个,依次为红花大金元,GY2、K326。     

切花玫瑰硼中毒症及其相关营养元素分析

针对云南省切花玫瑰主产区切花玫瑰营养枝叶片发生"叶缘灰褐色或枯焦斑块"的典型症状,开展了田间调查与室内分析研究。结果表明:该症是由于根际土壤有效B含量或切花玫瑰营养枝叶片B含量过高(分别大于3.41和164 mg/kg)引起的硼中毒症。相比正常切花玫瑰,硼中毒株营养枝及花枝的叶片N、P、K含量分别降低17.7%、31.1%、13.9%,Mg含量提高了38.4%,营养枝叶片Ca含量较高(3.168%),叶片的K/B、Ca/B、Mg/B值分别下降65.6%、66.2%、51.4%;不管是硼中毒株还是正常株,叶片的B含量均表现由营养枝至花枝逐渐降低,而K/B、Ca/B、Mg/B值则均表现逐渐提高的规律。据此说明,在切花玫瑰生产中应该重视平衡施肥。     

番木瓜植株镁钾含量变化与缺钾叶枯病的关系

采用田间调查、采样及其室内分析与田间试验相结合的方法,在低钾而高镁的土壤上,从植株各个部位探索番木瓜植株镁、钾营养变化对其生理性缺钾叶枯症的影响。结果表明,番木瓜叶枯症的发生,除与土壤有效钾缺乏有关外,Mg/K比值过高也是导致该症发生的一个重要原因。发生缺钾叶枯病的番木瓜植株,其根、茎、叶片、叶柄等器官含镁量均明显提高,施用钾肥后不但提高了植株的含K量,而且能抑制番木瓜植株对镁的吸收,从而协调平衡Mg/K比值,生理性缺钾叶枯症得到有效控制。     

不同年代采收的烟草种子农艺性状和经济性状的差异

为探索长期贮藏在云南烟草种质库的种子是否会发生遗传完整性和稳定性的变化,提出种子长期贮藏的安全指标.取出1979～2000年采收的红花大金元、K326和G-28共3个烤烟品种的种子共28份,分别进行苗期和大田期主要农艺性状观察,并对各经济性状指标进行比较.结果表明:苗期生长势与种子发芽势有关.发芽势较低的种子出苗缓慢,成苗期晚,反映到大田期产量和产值较低,烟叶品质较差.反之,发芽势较高的种子田间生长势强,可获得较高的产量和产值,原种较其他种子表现出较强的优势.同一品种不同年代生产的种子株高差异较大,叶数次之,茎围、节距相差不大.不同年代的红花大金元产量和上等烟比例无显著差异;产值、均价和级指差异显著.不同年代的K326除产量外的其他经济性状指标都有显著差异.各年度G-28产量、产值和上等烟差异显著,均价和级指无显著差异.通过这个试验,目前还没有发现明显的植物学特征的变化,也就是说,烟草种子在目前的条件下贮藏是安全的.     

不同营养配比对烤烟腺毛密度和石油醚提物含量的影响

通过烟株根部营养和叶面营养试验,研究了不同营养配比对烤烟腺毛密度和石油醚提物含量的影响。结果表明:不同营养配比对腺毛密度和石油醚提物含量均有一定的影响。在根部营养试验中,中、上部烟叶腺毛密度的差异均达到0.05显著水平,通过根部营养可以提高烟叶的腺毛密度,其中以配施饼肥处理的效果最好。中部叶石油醚提物含量的差异未达到0.05显著水平,说明烟叶腺毛密度与石油醚提物含量并不存在必然的联系,石油醚提物含量的高低可能还与烟株腺毛的分泌能力和生长环境有关。叶面营养的喷施同样可以提高烟株石油醚提物含量,其中以喷施醋酸 饼肥水 ZnSO4的效果最好。K326中下二棚烟叶腺毛密度变化幅度较大,其它叶位变化幅度较小。     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Relation between wheat-rye crossability and seed set of common wheat after pollination with other species in the Hordeae

Summary Cultivars of common wheat (Triticum aestivum L. em. Thell.) of high wheat-rye (Secale cereale L.) crossability set more seed with pollen of other related species than did wheats of low wheat-rye crossability. This was found to be true for pollen parents from the genera Triticum, Aegilops, Secale, Agropyron and Elymus.     

Mechanisms and diversity of resistance to sorghum shoot fly,Atherigona soccata

Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums.     

Reaction of tritordeum to Fusarium culmorum and Septoria nodorum

Summary Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases.     

Breeding apomictic bahiagrass (Paspalum notatum Flügge) with improved turf traits

The development of a turf‐type bahiagrass could have a remarkable impact on the billion‐dollar turf industry in the south‐eastern United States. The goals of this study were to (i) select bahiagrass genotypes with improved turf attributes and (ii) determine the reproductive mode and seed fertility of selected genotypes. The population included mutants, wild types, hybrids and standard cultivars evaluated at two locations for two years. Morphological variation was observed and clonal repeatability (H²) ranged from 0.27 to 0.90. Flowering was extremely reduced in some mutants, which also exhibited dark green colour, finer texture and reduced canopy height. Cytoembryological observations revealed that diploids reproduced sexually and tetraploids by obligate or facultative apomixis. Genotypes with superior seed fertility were identified, while others were comparable to the standard cultivars. While mutant plants exhibited great morphological variation, the random mutations did not affect their reproductive mode, validating the use of mutagenesis in apomictic species. The high H² indicated that selection for improved turf attributes could be successfully performed with the advantage of clonal seed propagation.     

Disease resistance in protected crops and mushrooms

Summary Cultivars of tomatoes, cucumbers, lettuce and peppers have been bred for resistance to one or more pathogens. Some tomato and cucumber cultivars have resistance to a wide range of diseases. Resistance has been transient in many cases and a succession of cultivars with new genes or new combinations of resistance genes has been necessary to maintain control. There has been a number of notable exceptions and these have included durable resistance to such pathogens asFulvia fulva and tomato mosaic virus. With lettuce the resistance situation is complicated by the occurrence of fungicide resistant pathotypes. There are no strains ofAgaricus bisporus purposely bred for disease resistance.In protected flower crops only resistance to Fusarium wilt in carnations has been purposely bred but differences in disease resistance are apparent in cultivars of many ornamental crops. This is particularly so in chrysanthemums where there are cultivars with resistance to many of the major pathogens. Similar situations occur with other flower crops and pot plants. Cultivars of some species have not been systematically investigated for resistance.The need for genetic resistance will increase with the further reduction, in the limits on pesticide use and an increasing public awareness and importance of pesticide pollution.ADAS is an executive agency of the Ministry of Agiculture, Fisheries and Food and the Welsh Office.     

Genetic constitution and diversity in four narrow endemic redwoods from the family Cupressaceae

The genetic constitution and diversity of four relictual redwoods are discussed in this review. These include monotypic genera of the family Cupressaceae: coast redwood (Sequoia sempervirens), giant sequoia (Sequoiadendron giganteum), dawn redwood (Metasequoia glyptostroboides), and alerce (Fitzroya cupressoides). All four species are narrow endemics, share a number of common phenotypic traits, including red wood, and are threatened species. Fossil history suggests that the ancestors of redwoods probably originated during the Cretaceous and Tertiary periods and flourished thereafter for millions of years. Towards the end of the Tertiary period began their decline and struggle for existence that continued during the subsequent geologic upheavals and climate changes, until the survival of the present-day redwoods in the current restricted locations in the world (USA, China, and South America). Although two species, Sequoiadendron and Metasequoia, are diploids (2n = 22), and the other two are polyploids: Fitzroya a tetraploid (2n = 4x = 44), and Sequoia a hexaploid (2n = 6x = 66); they all share the same basic chromosome number x = 11. The genome size in the hexaploid Sequoia is one of the largest (31,500 MB) in the conifers, while the genome sizes of diploid Metasequoia and Sequoiadendron are about one-third (~10,000 MB) of Sequoia. Genetic diversity in the redwoods is lower than most other gymnosperms, except in Sequoia, which seems to rank near the upper quarter of the coniferous forest trees. Genomic research is sparse in the redwoods, and should be pursued for a better understanding of their genome structure, function, and adaptive genetic diversity.     

Inheritance of fruit colour in a wild Russian red raspberry seedling

Summary A new gene, i, from a self-incompatible wild Russian Rubus idaeus seedling is described. The gene i interacts with the fruit colour gene T, Tii plants having apricot instead of red fruits, and spines, leaves and stems pigmented to varying degrees. A deficit of apricot-fruited seedlings in progenies segregating for i could be explained by linkage between i and the self-incompatibility S locus with a crossover value of approximately 26.7%.Segregations for spine colour in crosses and backcrosses of the Russian seedling with two green-spined (ttII) raspberries selected for their yellow fruit colour, showed that both the latter carried the spine colour intensifier gene P. This suggests that earlier authors were incorrect in attributing the apricot fruit colour developed by some tt plants to a pleiotropic effect of P.     

The induction in vitro of adventitious shoots in Rosa

Summary Adventitious shoots were formed on excised leaves, roots and callus of Rosa persica x xanthina and on excised leaves of R. laevigata and R. wichuraiana on culture media that included BAP and NAA as growth regulators. Shoots formed freely on freshly cultured callus of R. persica x xanthina but their production declined in successive cultures and ceased after twelve weeks. Transplantation to soil was improved by rooting plantlets in cellulose plugs in vitro and transferring plantlets to soil while still in the plugs.