Expected global suitability of coffee, cashew and avocado due to climate change.

Coffee, cashew and avocado are of high socio-economic importance in many tropical smallholder farming systems around the globe. As plantation crops with a long lifespan, their cultivation requires long-term planning. The evaluation of climate change impacts on their biophysical suitability is therefore essential for developing adaptation measures and selecting appropriate varieties or crops. In this study, we modelled the current and future suitability of coffee arabica, cashew and avocado on a global scale based on climatic and soil requirements of the three crops. We used climate outputs of 14 global circulation models based on three emission scenarios to model the future (2050) climate change impacts on the crops both globally and in the main producing countries. For all three crops, climatic factors, mainly long dry seasons, mean temperatures (high and low), low minimum temperatures and annual precipitation (high and low), were more restrictive for the global extent of suitable growing regions than land and soil parameters, which were primarily low soil pH, unfavourable soil texture and steep slopes. We found shifts in suitable growing regions due to climate change with both regions of future expansion and contraction for all crops investigated. Coffee proved to be most vulnerable, with negative climate impacts dominating in all main producing regions. For both cashew and avocado, areas suitable for cultivation are expected to expand globally while in most main producing countries, the areas of highest suitability may decrease. The study reveals that climate change adaptation will be necessary in most major producing regions of all three crops. At high latitudes and high altitudes, however, they may all profit from increasing minimum temperatures. The study presents the first global assessment of climate change impacts on cashew and avocado suitability.

Multifunctional potential of endophytic bacteria from Anacardium othonianum Rizzini in promoting in vitro and ex vitro plant growth.

Anacardium othonianum Rizzini, a cashew tree native to the Brazilian Cerrado, is economically important due to its applications in the food, chemical and pharmaceutical industries. However, A. othonianum yields a crop with low productivity due to a number of factors, such as nutritionally poor soils, drought and losses due to pests and diseases. Brazil is one of the nine largest cashew nut producers worldwide, and sustainable technologies are needed to increase the productivity of this crop. In this context, the use of endophytic microorganisms could promote plant growth and provide protection against phytopathogens. In this study, the isolation of the root endophytic community of A. othonianum led to the characterization of 22 distinct bacterial strains with multifunctional traits for plant growth promotion. The results of in vitro assays to assess auxin synthesis, phosphate solubilization, phosphatase and siderophore production and biocontrol against Fusarium oxysporum led to the selection of Acinetobacter lwoffii Bac109 and Pantoea agglomerans Bac131 as the most promising strains. The reinoculation of the Bac109 and Bac131 strains onto A. othonianum seeds showed that the treatment containing a mixture of these strains was the most effective in promoting increases in the biometric parameters of early plant growth. Thus, this study highlights the biotechnological potential of a consortium of A. lwoffii Bac109 and P. agglomerans Bac131 for future applications in sustainable cashew cultivation.

Anacardium Plants: Chemical,Nutritional Composition and Biotechnological Applications.

Anacardium plants are native to the American tropical regions, and Anacardium occidentale L. (cashew tree) is the most recognized species of the genus. These species contain rich secondary metabolites in their leaf and shoot powder, fruits and other parts that have shown diverse applications. This review describes the habitat and cultivation of Anacardium species, phytochemical and nutritional composition, and their industrial food applications. Besides, we also discuss the secondary metabolites present in Anacardium plants which display great antioxidant and antimicrobial effects. These make the use of Anacardium species in the food industry an interesting approach to the development of green foods.

UPLC-qTOF-MS/MS-based phenolic profile and their biosynthetic enzyme activity used to discriminate between cashew apple (Anacardium occidentale L.) maturation stages.

Cashew immature and ripe peduncles (Anacardium occidentale L.) from orange- and red-colored clones CCP 76 and BRS 189, respectively, were prepared as juice or fibrous fraction and submitted to UPLC-MS analyses, while the soluble fraction was also submitted to enzymatic evaluation. Cinnamoyl glucoside was present in ripe juice samples from both cashew clones, while monogalloyl diglucoside and digalloyl glucoside were present in immature juice samples from both cashew clones. Four compounds were found at immature fiber of both clones, anacardic acids (1, 2, 3) and GA19. The phenolic biosynthetic pathway was evaluated in juice samples and phenylalanine ammonia-lyase activity decreased significantly during the development, although it was much higher in ripe CCP 76. UDP-glycosyltransferases activity differed between clones, however its product cinnamoyl glucoside was a possible chemical marker of ripe juice samples from both clones. Flavonol synthase showed the highest specific activity in both cashew clones and its product, flavonols were identified in cashew apple at immature and ripe stages.

Oecophylla longinoda (Hymenoptera: Formicidae) Lead to Increased Cashew Kernel Size and Kernel Quality.

Weaver ants, Oecophylla spp., are known to positively affect cashew, Anacardium occidentale L., raw nut yield, but their effects on the kernels have not been reported. We compared nut size and the proportion of marketable kernels between raw nuts collected from trees with and without ants. Raw nuts collected from trees with weaver ants were 2.9% larger than nuts from control trees (i.e., without weaver ants), leading to 14% higher proportion of marketable kernels. On trees with ants, the kernel: raw nut ratio from nuts damaged by formic acid was 4.8% lower compared with nondamaged nuts from the same trees. Weaver ants provided three benefits to cashew production by increasing yields, yielding larger nuts, and by producing greater proportions of marketable kernel mass.

Global Potential Distribution of Bactrocera carambolae and the Risks for Fruit Production in Brazil.

The carambola fruit fly, Bactrocera carambolae, is a tephritid native to Asia that has invaded South America through small-scale trade of fruits from Indonesia. The economic losses associated with biological invasions of other fruit flies around the world and the polyphagous behaviour of B. carambolae have prompted much concern among government agencies and farmers with the potential spread of this pest. Here, ecological niche models were employed to identify suitable environments available to B. carambolae in a global scale and assess the extent of the fruit acreage that may be at risk of attack in Brazil. Overall, 30 MaxEnt models built with different combinations of environmental predictors and settings were evaluated for predicting the potential distribution of the carambola fruit fly. The best model was selected based on threshold-independent and threshold-dependent metrics. Climatically suitable areas were identified in tropical and subtropical regions of Central and South America, Sub-Saharan Africa, west and east coast of India and northern Australia. The suitability map of B. carambola was intersected against maps of fruit acreage in Brazil. The acreage under potential risk of attack varied widely among fruit species, which is expected because the production areas are concentrated in different regions of the country. The production of cashew is the one that is at higher risk, with almost 90% of its acreage within the suitable range of B. carambolae, followed by papaya (78%), tangerine (51%), guava (38%), lemon (30%), orange (29%), mango (24%) and avocado (20%). This study provides an important contribution to the knowledge of the ecology of B. carambolae, and the information generated here can be used by government agencies as a decision-making tool to prevent the carambola fruit fly spread across the world.

Seasonal Abundance of Mango Fruit Flies (Diptera: Tephritidae) and Ecological Implications for Their Management in Mango and Cashew Orchards in Benin (Centre & North).

We report the results of a large-scale (six orchards) and long-term (5-yr) study on seasonal population fluctuations of fruit flies (Diptera Tephritidae) in mango (2005-2009) and cashew (2007-2009) orchards in the Borgou Department, Benin.During the five consecutive years of mango fruit fly monitoring, 25 tephritid species were captured including three species of Bactrocera, 11 of Ceratitis, and 11 of Dacus, which is represented by 2,138,150 specimens in mango orchards. We observed significant differences in Bactrocera dorsalis (Hendel) counts between "high" and "low" mango production years from 2005 to 2008 but not in Ceratitis cosyra (Walker) counts. The native species, C. cosyra, the most abundant species during the dry season, peaked beginning of May, while the exotic species, B. dorsalis, the most abundant species during the rainy season, peaked in June. Preliminary results underlined the role of nine species of wild hosts and seven species of cultivated ones around mango orchards that played an important role in maintaining B. dorsalis in this Sudan zone all year round. The presence of C. cosyra stretched over 9 mo.During the first 14 wk of tephritid monitoring on cashew orchards situated near mango orchards, most flies (62%) were captured in traps positioned in cashew orchards, showing the strong interest of an early fly control on cashew before the mango season. According to these results, in the Sudan zone, effective and compatible control methods as proposed by the IPM package validated by the West African Fruit Fly Initiative project against mango fruit flies are proposed for a large regional tephritid control program in same zones of West Africa.

Insect fauna associated with Anacardium occidentale (Sapindales: Anacardiaceae) in Benin, West Africa.

Cashew, Anacardium occidentale L. (Sapindales: Anacardiaceae), is an important cash crop in Benin. However, its production is threatened by several biotic factors, especially insects. In Benin, very few studies have focused on insects and just listed species commonly found on cashew worldwide. The present investigation fills this gap by presenting an exhaustive inventory of insect species associated with this crop in the country. The survey was carried out from September 2009 to August 2010 in 22 cashew orchards (5 young and 17 mature) distributed over three major agroecological zones where cashew is most produced in the country. Insects were collected using chemical knock-down technique and visual observation followed by capture with sweep net. In addition, infested plant organs were sampled and incubated to collect emerging insects. In total, 262 insect species were recorded and identified. Among them, the wood borer Apate terebrans Pallas, the leafminer Eteoryctis gemoniella Stainton, and the mirid bugs Helopeltis schoutedeni Reuter., and Helopeltis anacardii Miller., appeared as the most important insect species attacking cashew in Benin. Beneficial insects encountered included some predators, parasitoids, and pollinators. Few vertebrate predators were also recorded on the trees. Differences in agroecological conditions or in field cleanliness did not affect the number of insect species encountered in the cashew orchards. The results of this study represent an important baseline data for the design and implementation of strategies for cashew protection in Benin.

Composting of cow dung and crop residues using termite mounds as bulking agent.

The present study reports the suitability of termite mounds as a bulking agent for composting with crop residues and cow dung in pit method. Use of 50 kg termite mound with the crop residues (stover of ground nut: 361.65 kg; soybean: 354.59 kg; potato: 357.67 kg and mustard: 373.19 kg) and cow dung (84.90 kg) formed a good quality compost within 70 days of composting having nitrogen, phosphorus and potassium as 20.19, 3.78 and 32.77 g kg(-1) respectively with a bulk density of 0.85 g cm(-3). Other physico-chemical and germination parameters of the compost were within Indian standard, which had been confirmed by the application of multivariate analysis of variance and multivariate contrast analysis. Principal component analysis was applied in order to gain insight into the characteristic variables. Four composting treatments formed two different groups when hierarchical cluster analysis was applied.

Salt-induced delay in cotyledonary globulin mobilization is abolished by induction of proteases and leaf growth sink strength at late seedling establishment in cashew.

Seedling establishment in saline conditions is crucial for plant survival and productivity. This study was performed to elucidate the biochemical and physiological mechanisms involved with the recovery and establishment of cashew seedlings subjected to salinity. The changes in the Na+ levels and K/Na ratios, associated with relative water content, indicated that osmotic effects were more important than salt toxicity in the inhibition of seedling growth and cotyledonary protein mobilization. Salinity (50mM NaCl) induced a strong delay in protein breakdown and amino acid accumulation in cotyledons, and this effect was closely related to azocaseinolytic and protease activities. In parallel, proline and free amino acids accumulated in the leaves whereas the protein content decreased. Assays with specific inhibitors indicated that the most important proteases in cotyledons were of serine, cysteine and aspartic types. Proteomic analysis revealed that most of the cashew reserve proteins are 11S globulin-type and that these proteins were similarly degraded under salinity. In the late establishment phase, the salt-treated seedlings displayed an unexpected recovery in terms of leaf growth and N mobilization from cotyledon to leaves. This recovery coordinately involved a great leaf expansion, decreased amino acid content and increased protein synthesis in leaves. This response occurred in parallel with a prominent induction in the cotyledon proteolytic activity. Altogether, these data suggest that a source-sink mechanism involving leaf growth and protein synthesis may have acted as an important sink for reserve mobilization contributing to the seedling establishment under salinity. The amino acids that accumulated in the leaves may have exerted negative feedback to act as a signal for the induction of protease activity in the cotyledon. Overall, these mechanisms employed by cashew seedlings may be part of an adaptive process for the efficient rescue of cotyledonary proteins, as the cashew species originates from an environment with N-poor soil and high salinity.

Agrobacterium tumefaciens-mediated transformation of Lasiodiplodia theobromae, the causal agent of gummosis in cashew nut plants.

Lasiodiplodia theobromae is a major pathogen of many different crop cultures, including cashew nut plants. This paper describes an efficient Agrobacterium tumefaciens-mediated transformation (ATMT) system for the successful delivery of T-DNA, transferring the genes of green fluorescent protein (gfp) and hygromycin B phosphotransferase (hph) to L. theobromae. When the fungal pycnidiospores were co-cultured with A. tumefaciens harboring the binary vector with hph-gfp gene, hygromycin-resistant fungus only developed with acetosyringone supplementation. The cashew plants inoculated with the fungus expressing GFP revealed characteristic pathogen colonization by epifluorescence microscopy. Intense and bright green hyphae were observed for transformants in all extensions of mycelium cultures. The penetration of parenchyma cells near to the inoculation site, beneath the epicuticle surface, was observed prior to 25 dpi. Penetration was followed by the development of hyphae within invaded host cells. These findings provide a rapid and reproducible ATMT method for L. theobromae transformation.

Natural forest biomass estimation based on plantation information using PALSAR data.

Forests play a vital role in terrestrial carbon cycling; therefore, monitoring forest biomass at local to global scales has become a challenging issue in the context of climate change. In this study, we investigated the backscattering properties of Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) data in cashew and rubber plantation areas of Cambodia. The PALSAR backscattering coefficient (σ0) had different responses in the two plantation types because of differences in biophysical parameters. The PALSAR σ0 showed a higher correlation with field-based measurements and lower saturation in cashew plants compared with rubber plants. Multiple linear regression (MLR) models based on field-based biomass of cashew (C-MLR) and rubber (R-MLR) plants with PALSAR σ0 were created. These MLR models were used to estimate natural forest biomass in Cambodia. The cashew plant-based MLR model (C-MLR) produced better results than the rubber plant-based MLR model (R-MLR). The C-MLR-estimated natural forest biomass was validated using forest inventory data for natural forests in Cambodia. The validation results showed a strong correlation (R2 = 0.64) between C-MLR-estimated natural forest biomass and field-based biomass, with RMSE  = 23.2 Mg/ha in deciduous forests. In high-biomass regions, such as dense evergreen forests, this model had a weaker correlation because of the high biomass and the multiple-story tree structure of evergreen forests, which caused saturation of the PALSAR signal.

Source-sink regulation of cotyledonary reserve mobilization during cashew (Anacardium occidentale) seedling establishment under NaCl salinity.

Seedling establishment is a critical process to crop productivity, especially under saline conditions. This work was carried out to investigate the hypothesis that reserve mobilization is coordinated with salt-induced inhibition of seedling growth due to changes in source-sink relations. To test this hypothesis, cashew nuts (Anacardium occidentale) were sown in vermiculite irrigated daily with distilled water (control) or 50mM NaCl and they were evaluated at discrete developmental stages from the seed germination until the whole seedling establishment. The salt treatment coordinately delayed the seedling growth and the cotyledonary reserve mobilization. However, these effects were more pronounced at late seedling establishment than in earlier stages. The storage protein mobilization was affected by salt stress before the lipid and starch breakdown. The globulin fraction represented the most important storage proteins of cashew cotyledons, and its mobilization was markedly delayed by NaCl along the seedling establishment. Free amino acids were mostly retained in the cotyledons of salt-treated seedlings when the mobilization of storage proteins, lipids and starch was strongly delayed. Proline was not considerably accumulated in the cotyledons of cashew seedlings as a response to NaCl salinity. According to these results it is noteworthy that the salt-induced inhibition of seedling growth is narrowly coordinated with the delay of reserve mobilization and the accumulation of hydrolysis products in cotyledons. Also, it was evidenced that free amino acids, especially those related to nitrogen transport, are potential signals involved in the regulation of storage protein hydrolysis during cashew seedling establishment under NaCl salinity.

Evaluation, grafting success and field establishment of cashew rootstock as influenced by VAM fungi.

Seven isolates of vesicular arbuscular mycorrhizal (VAM) fungi were isolated from cashew rhizosphere soil of different cashew growing regions of South India. These seven isolates along with two more VAM fungi namely Acaulospora laevis and Glomus mosseae, which were found to be better symbionts for cashew during our earlier study were used to study their effectiveness on the growth and nutrition of cashew rootstock Ullal-1. Four promising VAM fungi were selected based on this study. Rootstocks inoculated with these four fungi were evaluated for their vigour through grafting success, using Ullal-3 cashew variety as scion. Grafting success was more in rootstocks inoculated with A. laevis and one of local isolates Glomus etunicatum. Grafts with rootstock treated with G. etunicatum and A. laevis survived and performed better when planted in the field compared to the uninoculated and other VAM fungal treatments.

Proline accumulation and glutamine synthetase activity are increased by salt-induced proteolysis in cashew leaves.

In this study cashew (Anacardium occidentale) plants were exposed to a short- and long-term exposure to NaCl in order to establish the importance of the salt-induced proteolysis and the glutamine synthetase activity on the proline accumulation. The cashew leaf showed a prominent proline accumulation in response to salt stress. In contrast, the root tissue had no significant changes in proline content even after the drastic injury caused by salinity on the whole plant. The leaf proline accumulation was correlated to protease activity, accumulation of free amino acid and ammonia, and decrease of both total protein and chlorophyll contents. The leaf GS activity was increased by the salt stress whereas in the roots it was slightly lowered. Although the several amino acids in the soluble pool of leaf tissue have showed an intense increment in its concentrations in the salt-treated plants, proline was the unique to show a proportional increment from 50 to 100 mol m-3 NaCl exposure (16.37 to 34.35 mmol kg-1 DM, respectively). Although the leaf glutamate concentration increased in the leaves of the salt-stressed cashew plants, as compared to control, its relative contribution to the total amino acid decreased significantly in stressed leaves when compared to other amino acids. In addition, when the leaf discs were incubated with NaCl in the presence of exogenous precursors (Glu, Gln, Orn or Arg) involved in the proline synthesis pathways, the glutamate was unique in inducing a significant enhancement of the proline accumulation compared to those discs with precursor in the absence of NaCl. These results, together with the salt-induced increase in the GS activity, suggest an increase in the de novo synthesis of proline probably associated with the increase of the concentration of glutamate. Moreover, the prominent salt-induced proline accumulation in the leaves was associated with the higher salt-sensitivity in terms of proteolysis and salt-induced senescence as compared to the roots. In conclusion, the leaf-proline accumulation was due, at least in part, to the increase in the salt-induced proteolysis associated with the increments in the GS activity and hence the increase in the concentration of glutamate precursor in the soluble amino acid pool.