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931.
Sarika Mathure Asif Shaikh N. Renuka Kantilal Wakte Narendra Jawali Ratnakar Thengane Altafhusain Nadaf 《Euphytica》2011,179(2):237-246
Eighty-eight aromatic cultivars collected from Maharashtra state were assessed for determinants of kernel quality (kernel
size-shape, test weight and aroma) and grain morphology such as awning, lemma and palea characters, pubescence, colour of
sterile lemma and apiculus colour. We, report seven cultivars—‘Girga’, ‘Kothmirsal’, ‘Kala bhat’, ‘Chimansal’, ‘Jiri’, ‘Kalsal’
‘Velchi’ and ‘Kali kumud’ as indigenous to southern India. Of the 69 cultivars characterized for agronomic traits 36 cultivars
were exquisite genotypes and possessed one or more superior traits such as early flowering, dwarf stature, higher number of
productive tiller per plant; long panicles; higher number of filled grains per panicle and strong aroma. Variability in aromatic
cultivars was assessed on the basis of nine traits placed aromatic rice cultivars in five clusters. Number of cultivars in
each cluster ranged from 1 to 33. 27 significant correlations were obtained in the physical, agronomic and grain morphology
traits. Aroma was found to be negatively associated with days to 50% flowering as well as with filled grains per panicle.
However, correlation between panicle length and effective tillers with aroma was not observed. Therefore, to increase the
yield, improvement in length of panicle and increasing number of productive tillers in medium or mild scented cultivars would
be the best strategy. 相似文献
932.
Yuuri Hirooka Takao Kobayashi Jun Takeuchi Tsuyoshi Ono Yasunori Ono Keiko T. Natsuaki 《Journal of General Plant Pathology》2007,73(5):330-335
A ring spot disease of Aloe vera was found on leaves of potted seedlings of Aloe vera in Hachijojima and Chichijima Islands, Tokyo. From tissue of ring spot lesions, a fungus producing Fusarium-type conidia was consistently isolated. After 1 month, reddish perithecia of nectriaceous fungus had formed on the colonies
of this isolate on PDA. These nectriaceous and Fusarium fungi were identified as Haematonectria haematococca and Fusarium sp., respectively. From a single ascospore isolation, the former was confirmed to be the teleomorph of the Fusarium sp. Typical ring spot lesions were reproduced by artificial inoculations using single ascospore and single conidium isolates.
Inoculations of five species of genus Aloe revealed that they were highly susceptible except for A. arborescens. This is the first report of a disease on Aloe caused by H. haematococca (anamorph: Fusarium sp.) in Japan, and it was named aloe ring spot. 相似文献
933.
Atiqur Rahman Barbhuiya Ayyanadar Arunachalam Prabhat Chandra Nath Mohammed Latif Khan Kusum Arunachalam 《Journal of Forest Research》2008,13(1):25-34
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species
(Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea,
Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied
significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression
equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight
loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively
faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content,
lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature,
and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other
different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition
rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling. 相似文献
934.
This study examined the effects of contact with wood on the living human body using a physiological index and subjective evaluation.
Consecutive blood pressure measurements were used as the physiological index, and sensory evaluation using the semantic differential
(SD) method was used for subjective evaluation. Consideration was also given to cases in which materials were cooled and heated
as well as kept at room temperature, to eliminate the effects of heat flux due to differences in thermal conductivity between
wood and other materials. It was found that contact with wood produced coarse/natural sensations, with no associated increase
in systolic blood pressure. Contact with cold wood created subjectively dangerous/uncomfortable but still coarse/natural sensations,
also with no associated increase in blood pressure; therefore, there was no correspondence between subjective evaluation and
physiological responses. Contact with aluminum kept at room temperature and cold acrylic plastic created flat/artificial and
dangerous/uncomfortable sensations, with an associated significant increase in blood pressure; thus, there was a close correlation
between subjective evaluation and physiological responses. It was therefore concluded that contact with wood, unlike artificial
materials such as aluminum, induces no physiological stress even when kept at room temperature or cooled.
Part of this report was presented at the 48th Annual Meeting of the Japan Wood Research Society in Shizuoka, April 1998 相似文献
935.
936.
Umma Tamima 《林业研究》2016,27(4):853-861
The objective was to evaluate the performance of the co-management of Nishorgo Support Project at Chunati Wildlife Sanctuary in Bangladesh. I adopted the Focus Groups Discussion method for opinion survey and applied the SWOTAHP technique for data analysis. Local people did not participate in the decision-making process of forest management and they perceived co-management as a threat to their livelihoods. Moreover, mistrust and misunderstanding among different stakeholders, political and ethical conflicts, lack of property rights of tribal communities, and lack of accountability and transparency were identified as the drawbacks of co-management. 相似文献
937.
Salwinder S. Dhaliwal Gurpal S. Toor Ignacio A. Rodriguez-Jorquera Todd Z. Osborne Susan Newman 《Journal of Soils and Sediments》2018,18(2):342-351
Purpose
Inorganic contaminants present a major challenge for the restoration of aquatic ecosystems. The objectives of this study were to determine the extent of trace metal contamination and investigate the influence of different plant communities on trace metal accumulation in the soils of the Florida Everglades.Materials and methods
Soil samples (n?=?117) were collected from 0 to 10-cm depth using a stainless steel coring device from sites with three dominant plant communities—cattail, sawgrass, and slough—of Water Conservation Area-2A (43,281 ha) of Florida Everglades.Results and discussion
The mean pH in soils collected from three plant communities was 6.75–6.82, whereas electrical conductivity was slightly greater in the sawgrass (0.69 dS m?1) than cattail (0.58 dS m?1) and slough (0.40 dS m?1). Mean reduction–oxidation potential was greatest in cattail (?113 mV) than sawgrass (?85.3 mV) and slough (?48.3 mV) soils. Among 11 trace metals (As, B, Co, Cr, Cu, Mn, Mo, Na, Ni, Pb, Zn) found in soil samples, Na had the greatest contents and was greater in cattail (2070 mg kg?1) and sawgrass (1735 mg kg?1) than slough (1297 mg kg?1). Four trace metals (B, Cu, Mo, Ni) were significantly greater in cattail than sawgrass and slough. Whereas, Mn was significantly lower in cattail (31 mg kg?1) than both sawgrass (84 mg kg?1) and slough (51 mg kg?1). Cattail also had significantly lower Cr (1.97 mg kg?1) and Pb (10 mg kg?1) than sawgrass (Cr 2.5 mg kg?1; Pb 20.8 mg kg?1). As (<6.9 mg kg?1), Co (<1.3 mg kg?1), and Zn (<17.2 mg kg?1) were not significantly different among soils collected from three plant community-dominant sites. Contents of Cd and Se were below the method detection limits (Cd 0.01 mg L?1; Se 0.2 mg L?1) and are not reported.Conclusions
None of the trace metals in the soils exceeded the US Environmental Protection Agency sediment toxicity thresholds. Results from this study provided baseline concentrations of trace metals, which can be used to measure the success of restoration efforts in Florida Everglades.938.
Paula Martins-Lopes José Lima-Brito Sónia Gomes Julieta Meirinhos Luís Santos Henrique Guedes-Pinto 《Genetic Resources and Crop Evolution》2007,54(1):117-128
Thirty Portuguese and eight foreign olive (Olea europaea L.) cultivars were screened using Random Amplified Polymorphic DNA (RAPD) and Inter-Simple Sequence Repeat (ISSR) markers.
Twenty RAPD primers amplified 301 reproducible bands of which 262 were polymorphic; and 17 ISSR primers amplified 204 bands
of which 180 were polymorphic. The percentage of polymorphic bands detected by ISSR and RAPD was similar (88 and 87%, respectively).
The genetic variability observed was similar in the Portuguese and foreign olive cultivars. Seven ISSR and 12 RAPD primers
were able to distinguish individually all 38 olive cultivars. Twenty specific molecular markers are now available to be converted
into Sequence Characterised Amplified Region (SCAR) markers. Relationships among Portuguese and foreign cultivars is discussed. 相似文献
939.
Olawale Mashood Aliyu Oluwayemisi Oluwatosin Adeigbe Joshua Adedokun Awopetu 《Journal of Crop Science and Biotechnology》2011,14(2):143-150
The problem of declining tree yield has led to an investigation into the effectiveness of foliar application of exogenous
hormones to improve flowering, fruit set, and fruit retention in cashew. Five exogenous hormones, one Gibberellic Acid (GA3) and four Auxins (IAA, IBA, NAA, and 2,4-D) at seven different rates of application (0 mg L−1, 10 mg L−1, 25 mg L−1, 50 mg L−1, 100 mg L−1, 250 mg L−1, and 500 mg L−1) were tested on six yield-related components of the two Brazilian cashew genotypes. This trial was a factorial split-split-plot
design with each treatment replicated five times within a tree and three replications (three trees) per genotype. Responses
varied significantly between exogenous hormones, concentrations and genotypes. The cashew plants used showed hormone-specific
and optimum concentration response patterns. Of the five exogenous hormones tested, GA3 was most effective as its application at 50–100 mg L−1 gave five-fold improvements in flowering (precocity and number of hermaphrodite flowers) and fruiting, and about 69% increase
in fruit retention ability and 25% in nut size. Panicles treated with GA3 also produced relatively bigger nuts compared to the untreated. Days to flowering was found to be hormone sensitive, while
production of hermaphrodite flowers, fruit set, and nut development tended to be concentration specific. The GA3 exhibited a broad concentration tolerance among the five exogenous hormones investigated. Our data showed that using GA3 at 50 mg L−1 will enhance flowering precocity, shorten flowering duration, increase production of hermaphrodite flowers and fruit set
significantly, and resultant nuts develop optimally with high percentage retention. Thus, it suggests cashew yield could be
increased by exogenous foliar application of GA3 at 50–100 mg L−1 at pre-blooming stage. 相似文献
940.
Mostafa M. Rady Mohamed A. Seif El-Yazal Hanan A. A. Taie Safia M. A. Ahmed 《Journal of Crop Science and Biotechnology》2016,19(5):363-371
Polyamines [i.e. spermine (Spm), spermidine (Spd) and putrescine (Put)] antagonistic effects on stress imposed by 2.0 mM lead (Pb2+) on growth, yield and its components and changes in the osmoprotectant and endogenous Pb2+ concentrations, the contents of some nutrients and tissue health in wheat plants were evaluated. Under the three applied polyamine (PAs) applications, the efficiency of wheat plants to tolerate Pb2+ stress in terms of growth and yield characteristics was noticed to varying degrees. The enhancements in osmoprotectant concentrations and plant health [in terms of relative water content (RWC) and membrane stability index (MSI)], and reductions in electrolyte leakage (EL) and plant Pb2+ concentration were correlated with the reasonable growth of Pb2+-stressed plants and their grain yield. Results point out that, better growth and yield characteristics, MSI, RWC, leaf photosynthetic pigment and osmoprotectant concentrations, and nutrient contents were obtained with seed soaking in 0.25 mM Spm, 0.50 mM Spd or 1.0 mM Put than those generated with seed soaking in water under 2.0 mM Pb2+ stress. In contrast, EL and the concentration of endogenous Pb2+ were significantly reduced. However, the Pb2+-free control positively exceeded the all stressed treatments. Among all tested PAs, 1.0 mM Put showed the best results and thus is recommended, as seed soaking, for wheat to grow well under Pb2+ stress. 相似文献