The Pathosystem Solanum tuberosum L.-Phytophthora infestans (Mont.) de Bary in Chapingo,Mexico. Expected,Observed, and Simulated

The 1:1 ratio of the Phytophthora infestans A1 and A2 mating types favors the sexually derived genetic diversity of the late blight pathogen of potatoes, which is widespread in the central highlands of México. This ratio guarantees the successful infection of this pathogen, even in resistant potato hosts. However, wild Solanum species present in the region serve as alternative hosts to the pathogen. Knowledge about the external factors that influence the dynamics of this disease facilitates the assessment and selection for genetically resistant potato cultivars to late blight, in addition to providing the capacity to predict epidemics. This work aimed to assess the expected, observed, and simulated progress of natural P. infestans infection of potatoes during two epiphytotic field seasons (2009 and 2010) at Chapingo, México. Using 8-years of weather datasets, six ideal situations were predicted with four to eight infection cycles of 6 to 12 h each. In comparison to the predictions, the observed effect of the area under the disease progress curve, and its components (AUDPC, RAUDPC, RaRAUDPC), was highly significant, with a low coefficient of variation among the potato cultivars used in the study. In conclusion, we confirm that the LATEBLIGHT-LB2004 model is useful for simulating and predicting late blight epidemics based on the weather conditions of Chapingo, except for the magnitude of the relative humidity threshold variable (RH_threshold), which requires calibration for each cultivar.     

Quick-cooking beans (Phaseolus vulgaris L.): II. Phytates,oligosaccharides, and antienzymes

Effects of the quick-cooking processes on phytate and oligosaccharide levels, and on trypsin and chymotrypsin inhibitors, were investigated in three bean varieties (Phaseolus vulgaris L.: Great Northern, red kidney, and pinto). Beans soaked in distilled water had lower levels of phytate-P than those soaked in a mixed salt solution. Leaching losses of oligosaccharides were nearly the same in different soaking treatments for all the beans except kidney beans. Residual trypsin inhibitor activities (TIA) in cooked quick-cooking beans were about 10% compared with about 20% for chymotrypsin inhibitor activities (CTIA) in the same bean products. -Irradiation was more effective in reducing TIA than CTIA and paralleled destruction by moist heat.Utah Agricultural Experiment Station Journal article no. 2480.     

大叶茶（Camellia sinensis var. assamica）的命名、模式及自然分布

大叶茶（Camellia sinensis var. assamica）在全球广泛种植,是商品茶叶的重要原料来源。本文系统地回顾了大叶茶学名的合格发表及其命名模式的研究进展。依据《深圳法规》条款41.4,Griffith在1854年将茶组[Camellia sect. Thea (L.) Griff.]作为新等级名称、而非新类群名称合格发表。老挝茶因其叶背具腺点、花柱离生而被移出茶组。Masters在1844年并未合格发表Thea assamica,此名称最早由Hooker于1847年合格发表,Steenis于1949年提出的新组合Camellia sinensis (L.) Kuntze var. assamica (Hook.) Steenis应为大叶茶的完整学名。英国邱园馆藏标本W. Griffith s.n.（K000939670）在2021年被指定为大叶茶的新模式。本文同时总结了迄今归并的7个大叶茶的异模式异名的原白和模式。尽管Darlington和Ammal在1945年将大叶茶作为物种处理并提出新组合名称C. assamica,多学科证据却支持大叶茶是茶的变种。假如大叶茶的物种地位被接受,那么1838年发表的大叶茶的异模式异名C. theifera将取代C. assamica而获得物种阶元上的优先权,届时,广泛使用的种加词“assamica”或可依据《深圳法规》条款14提议作为保留名称。本文同时总结了大叶茶在中国、印度、老挝、缅甸、泰国和越南的自然分布点,并讨论了它在不同原产国的自然资源的保护和利用现状。     

A Medicinal Halophyte Ipomoea pes-caprae (Linn.) R. Br.: A Review of Its Botany,Traditional Uses,Phytochemistry, and Bioactivity

Ipomoea pes-caprae (Linn.) R. Br. (Convolvulaceae) is a halophytic plant that favorably grows in tropical and subtropical countries in Asia, America, Africa, and Australia. Even though this plant is considered a pan-tropical plant, I. pes-caprae has been found to occur in inland habitats and coasts of wider areas, such as Spain, Anguilla, South Africa, and Marshall Island, either through a purposeful introduction, accidentally by dispersal, or by spreading due to climate change. The plant parts are used in traditional medicine for treating a wide range of diseases, such as inflammation, gastrointestinal disorders, pain, and hypertension. Previous phytochemical analyses of the plant have revealed pharmacologically active components, such as alkaloids, glycosides, steroids, terpenoids, and flavonoids. These phytoconstituents are responsible for the wide range of biological activities possessed by I. pes-caprae plant parts and extracts. This review arranges the previous reports on the botany, distribution, traditional uses, chemical constituents, and biological activities of I. pes-caprae to facilitate further studies that would lead to the discovery of novel bioactive natural products from this halophyte.     

Glands,essential oils and in vitro establishment of Helichrysum italicum (Roth) G. Don ssp. microphyllum (Willd.) Nyman

In this work, two Helichrysum italicum (Roth) G. Don ssp. microphyllum (Willd.) Nym. genotypes (genotype 1 and genotype 12) collected from different areas of Corsica were used. After the taxonomic identification based on several specific morphological characters, the two genotypes were subjected to microscopic studies. The precise structure of the glandular trichomes, secreting essential oils, on the flower heads and leaves of H. italicum (Roth) G. Don ssp. microphyllum (Willd.) Nym. are described here for the first time. Volatile constituents from both field-grown genotypes 1 and 12 were analyzed and their composition compared: monoterpenes were the most abundant class of compounds with nerol and its esters as the main metabolites. Genotype 12 was used to establish an efficient micropropagation protocol. For proliferation, different concentrations of 6-benzylaminopurine (BAP) alone or in combination with indole-3-butyric acid (IBA) were tested adding sucrose (20% or 30%). To define the optimal conditions for in vitro rooting, the shoots obtained were divided and transferred to the culture medium without growth regulators or enriched by different auxins in combination with sucrose (20% or 30%). Acclimatization, carried out in different conditions was easy, registering high survival percentages. The results achieved in this study allowed to obtain selected and standardized plants suitable for the exploitation in industrial sectors of this interesting species.