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Typhoons are destructive multi-hazard events. To assess the relationship between typhoon intensity and agricultural loss, there is a need for accurate and standardized information on loss and damage, which is currently lacking. To address this, a database for Vietnam and the Philippines was created to provide aggregated information on the magnitude of rice damage and to highlight the rice-growing areas which were prone to being damaged by typhoons. Our study period was from 1970 to 2018, and we focused on Vietnam and the Philippines as these two countries experience frequent and intense typhoons. As different crops respond differently to wind and rain, we limit our research to a single crop. In this study, we focused on rice as it is a major staple food in Southeast Asia, and rice fields were often damaged by typhoons in the two countries. Of the 829 typhoon events recorded, only 15% of the events resulted in rice damage. The average area of rice damaged per typhoon event ranged from 42,407 ha in Vietnam to 83,571 ha in the Philippines. Meanwhile, the average production loss per typhoon event ranged from 190,227 metric tonnes in the Philippines to 539,150 metric tonnes in Vietnam. The monetary value of rice crops lost was only reported in the Philippines, and this amounted to an average of US$ 42 million per typhoon event. There was a weak relationship between landfall wind speed and the three indicators of rice damage, which suggests that rice damage was not primarily due to strong winds. Our results showed that the rice fields in the coastal provinces of Vietnam and the northern parts of the Philippines were more vulnerable to being damaged by typhoons. [ABSTRACT FROM AUTHOR]

Yam is one of the agricultural crops known and has great economic importance in many African and Asian countries, the most important of which is the production of starch and flour. Therefore, it is an alternative to wheat in the manufacture of bread, and successful cultivation of yam crop in warm areas, which means the possibility of growing large-scale in Egypt to contribute significantly to bridging the food gap in wheat. To study the effects of application of gibberellic acid (GA3) and benzyladinine (BA) on yam tubers dormancy and subsequent sprouting, pot experiment was done. To determinate the most appropriate dates for planting in Egypt and the best level of potassium for the highest productivity field experiment was conducted at the Experimental farm of Vegetable Crops and Medicinal and Aromatic plants Research Institute. Agriculture Research Center. Dokki, Giza, during the period of 2016/2017 and 2017/2018. The experimental design a split plot design with three replicates was used. The main plot was three different planting dates (1st May, 1st June and 1st July. The sub plot was three levels of potassium fertilizer (96, 144, 192 Kform of potassium sulphate (48% K2O) and control treatment (without adding potassium fertilizer). The highest sprouting % (100%) was obtained with 1.0 mg/l BA. The combination between K2O at 144 kg/fed with 1st June swing date gave the highest vine length, leaf area, Total chlorophyll, total yield/fed and total yield/ha of both seasons. [ABSTRACT FROM AUTHOR]

Storms cause major forest disturbances in Europe. The aim of this study was to model tree-level storm damage probability based on the properties of a tree and its environment and to examine whether fine-scale topographic information is connected to the damage probability. We used data documenting effects of two autumn storms on over 17 000 trees on permanent Finnish National Forest Inventory plots. The first storm was associated with wet snowfall that damaged trees, while exceptionally strong winds and gusts characterized the second storm. During the storms, soils were unfrozen and deciduous trees were without leaves. Generalized linear mixed models were used to study how topographical variables calculated from digital elevation models (DEM) with resolutions of 2 and 10 m (TOPO2 and TOPO10, respectively) were related to damage probability, in addition to variable groups for tree (TREE) and stand (STAND) characteristics. We compared models containing different variable groups with Akaike information criteria. The best model contained the variable groups TREE, STAND, and TOPO2. Increase in slope steepness calculated from the high-resolution DEM decreased tree-level damage probability significantly in the model. This suggests that the local topography affects the tree-level damage probability and that high-resolution topographical data improves the tree-level damage probability models. [ABSTRACT FROM AUTHOR]

Frequent intermediate disturbances can produce qualitatively different spatial heterogeneity and environmental variability than large infrequent disturbances, which facilitates the coexistence of disparate species types. We hypothesized that species coexistence will be maximized at sites exposed to recurring hurricanes with intermediate frequencies and effects. Consequently, we sought to determine if exposure vulnerability (EV) from three hurricanes with intermediate effects and frequencies (Ivan-2004, Dennis-2005 and Dean-2007), or the interaction between exposure and topography, could be used to explain forest structural dynamics and composition. We used data obtained in 2006 and 2012 from within 45, 25 × 25 m (2.8125 ha) permanent sample plots, established according to a randomized block design, and stratified according to elevation and aspect/sites (NE and SW facing ridges) in a tropical montane wet forest, John Crow Mountains, Jamaica. There was a significant reduction in basal area (BA) (14%), tree volume (10%), and density (26%) and there was a negative shift in the height profile of trees. Understory light (2008), stem density, and mortality increased with EV but decreased with aspect. The NE aspect/sites had higher EV after Dean and the other hurricanes. Consequently, BA, volume and density increased significantly for light-demanding species at the NE sites, but declined significantly overall with minimal changes at SW sites. Moreover, diversity was significantly higher at sites with higher EV for the three hurricanes. The frequent hurricanes with intermediate effects may have therefore maintained/increased spatial heterogeneity, which promoted the coexistence of species with disparate life histories at more exposed sites. [ABSTRACT FROM AUTHOR]

A rapid, robust, and economical method to detect hailstorm-damaged olive fruit ( Olea europaea L.) would benefit both consumers and producers of olives and olive oil. Here, the feasibility of using Near-Infrared (NIR) spectroscopy for olive fruit sorting (cv. Canino) into hailstorm-damaged and undamaged classes is demonstrated. Features selected from the entire spectra by the genetic algorithm (two to six features per model) were input to Linear Discriminant Analysis, Quadratic Discriminant Analysis and k-Nearest Neighbor routines to develop models to classify olive fruit. Spectral pretreatment and feature selection were optimized through an iterative routine developed in R statistical software. Each model was evaluated based on false positive (α-error), false negative (β-error) and total error rates. The most accurate models yielded total error rates of less than five percent. The optimal features corresponded to R [1320 nm], R [∼1460 nm], R [∼1650 nm], R [∼1920 nm], R [∼2080 nm], R [∼2200 nm] and R [∼2220 nm], where R [x] represents the reflectance of light from the sample at a wavelength of x nm. The results indicate that single-point NIR spectroscopy is a feasible basis for hailstorm damage detection in olive fruit with the potential to allow on-line implementation on milling production lines. [ABSTRACT FROM AUTHOR]

The present investigations were carried to evaluate the trapping efficiency of three different yellow sticky traps for monitoring of aphid population in groundnut with relation to weather factors. The aphid population was found comparatively higher during January to March every year. The number of aphid (alates) caught was significantly higher on inverted dust bin traps followed by round plate traps and rectangular tray trap. [ABSTRACT FROM AUTHOR]

There is a growing emphasis on preserving ecological resilience, or a system's capacity to absorb or recover quickly from perturbations, particularly in vulnerable coastal regions. However, the factors that affect resilience to a given disturbance are not always clear and may be system-specific. We analyzed and synthesized time series datasets to explore how extreme events impacted a large system of submersed aquatic vegetation (SAV) in upper Chesapeake Bay and to identify and understand associated mechanisms of resilience. We found that physical removal of plants around the edge of the bed by high flows during a major flood event as well as subsequent wind-driven resuspension of newly deposited sediment and attendant light-limiting conditions were detrimental to the SAV bed. Conversely, it appears that the bed attenuated high flows sufficiently to prevent plant erosion at its inner core. The bed also attenuated wind-driven wave amplitude during seasonal peaks in plant biomass, thereby decreasing sediment resuspension and increasing water clarity. In addition, clear water appeared to 'spill over' into adjacent regions during ebb tide, improving the bed's capacity for renewal by creating more favorable growing conditions in areas where plant loss had occurred. These analyses demonstrate that positive feedback processes, whereby an SAV bed modifies its environment in ways that improve its own growth, likely serve as mechanisms of SAV resilience to flood events. Although this work focuses on a specific system, the synthetic approach used here can be applied to any system for which routine monitoring data are available. [ABSTRACT FROM AUTHOR]

Extreme weather events like high solar radiation can cause stress in apple fruits ( Malus domestica Borkh.). The aim of the study was to make a screening of individual phenols and peroxidase activity in apple peel as a response to sunburn and different sun-exposures in the period when weather conditions are suitable for sunburn occurrence. Apple fruits of ‘Golden Delicious’ and ‘Braeburn’ were sampled. Fruit temperature and color were measured prior HPLC–MS 2 and peroxidase activity analyses. Sunburned peel was darker and more yellow-red in comparison to healthy peel, which appeared yellow-green. Fruit temperature, total as well as individual flavonols and dihydrochalcones, total hydroxycinnamics and perixodase activity were highest in sunburned peel in comparison with healthy sun-exposed peel, furthermore both were different than shaded sides of both fruits and peel of apples inside the tree crown; moreover in sunburned peel dihydrochalcones were determined for the first time. Chlorogenic acid was up to 2.5 times higher, 3-hydroxy-phloretin-2′- O -xyloglucoside was up to 10 times higher and quercetin-3-galactoside was up to 33 times higher in sunburned peel, comparing to shaded sided peels. Flavanols did not show a distinct pattern. A deeper insight in phenolic response against environmental stress caused by high solar radiation and high air temperatures has been made. [ABSTRACT FROM AUTHOR]

Question Hurricanes are a major factor influencing forest structure and have been linked to higher incidences of multiple-stemmed trees in Caribbean dry forests relative to the continent. In Sept 1998, category 3 Hurricane Georges passed over Mona Island. This island, unlike others in the Caribbean, has had feral goats for five centuries. In this study we addressed the following questions: (i) what are the short-term (4 mo) and long-term (10 yr) responses of Mona Island's dry forests to hurricane disturbance in terms of forest structure and tree mortality; and (ii) is there any effect of goat exclusion on the recovery process and forest structure after the hurricane? Location Dry forest of Mona Island, Puerto Rico. Methods Permanent fenced and unfenced plots established in 1997 and monitored annually until 2008 were used to evaluate the interplay between goat herbivory and hurricane effects on structural dynamics of the tree community. Within these plots, vegetation data collected include species identity, DBH, successional status and hurricane-related tree mortality. Results We found that vegetation responses to hurricane disturbances may have been influenced by the presence of feral goats through at least two mechanisms. First, goats may have led to changes in forest structure and composition that feed back into the recovery dynamics that follow hurricane events. Second, goat herbivory limits the production of multiple stems, a trait that could be an adaptive response in hurricane-prone areas. Feral goats may lead to alternate successional pathways by keeping this dry forest at early-successional stages much longer than expected, and shifting vegetation communities to an alternate state where smaller, shrubbier and perhaps less palatable species dominate. Conclusions Differences in structure between Mona Island's dry forest and other tropical dry forests are related to changes in species composition that may have been triggered by introduced goats. Our results highlight the potential complexities that may arise when setting management goals within the context of novel ecosystems. Ultimately, implementation of management goals requires knowing what changes are linked to the ecological integrity of the ecosystem and what cultural values are placed on the current state of the tree community vs its historical condition. [ABSTRACT FROM AUTHOR]

Priming can improve plant innate capability to deal with the stresses caused by both biotic and abiotic factors. In this study, the effect of DL-β-amino-n-butyric acid (BABA) against Aphis glycines Matsumura, the soybean aphid (SA) was evaluated. We found that 25 mM BABA as a root drench had minimal adverse impact on plant growth and also efficiently protected soybean from SA infestation. In both choice and non-choice tests, SA number was significantly decreased to a low level in soybean seedlings drenched with 25 mM BABA compared to the control counterparts. BABA treatment resulted in a significant increase in the activities of several defense enzymes, such as phenylalanine ammonia-lyase (PAL), peroxidase (POX), polyphenol oxidase (PPO), chitinase (CHI), and β-1, 3-glucanase (GLU) in soybean seedlings attacked by aphid. Meanwhile, the induction of 15 defense-related genes by aphid, such as AOS, CHS, MMP2, NPR1-1, NPR1-2, and PR genes, were significantly augmented in BABA-treated soybean seedlings. Our study suggest that BABA application is a promising way to enhance soybean resistance against SA. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to determine the survival of small sea oats seedlings and large vegetative sea oats plants at beaches with low dune profiles. It mentions that survival of sea oats seedlings and vegetative plants were similar at normal beach conditions but vegetative plants survived better after storm surge events. It cites that seedlings would survive better in environments experiencing less storm surge unlike vegetative plants which are stronger.

The article offers information on the monograph titled "Researches on Irritability of Plants" by biologist Jagadis Chandra Bose published in 1913. According to Bose, plants are affected by storm, sunshine, drought and rain. Bose states that for the study of excitatory reactions of the plant, time elapses between the incidents of the shock and the initiation of a responsive movement should be determined.

The article offers the author's insights on his collection of African violets and the challenges he faced while reassembling his collection after the bad weather. Topics discussed by the author include the implication of bad weather to African violets, the desperate measures he adopted for some of his old varieties to prevent their decline, and the use of traditional planting techniques to maintain his old varieties like Saintpaulia ionantha, Violet Beauty, and Pink Beauty.