Alleviating the adverse effects of deficit irrigation in Flame seedless grapevine via Paulsen interstock

Using interstock with a potential genetic base is considered more recent and sustainable strategy for mitigating the water deficit. This investigation was carried out on transplant of Flame seedless (Vitis vinifera) grapevine grafted onto two rootstocks namely; Freedom (Vitis champinii x 1613C) and 1103Paulsen (vitis berlandieri x Vitis rupestris) with or without 1103Paulsen as interstock to determine its performance under deficit irrigation condition (50% of field capacity). The results indicated that Paulsen as rootstock or as interstock significantly increased the growth vigor of Flame seedless scion as well as the leaf content of total proline, phenols and sugars. Paulsen rootstock has decreased stomatal conductance, leaf transpiration rate and increased diffusion resistance under 50% deficit irrigation compared with grafting on Freedom rootstock. Moreover, Paulsen as interstock for Flame seedless grafted onto Freedom rootstock significantly increased relative water content accompanied by an increase in thickness of leaf anatomical characters such as midvein, lamina, palisade, xylem and phloem tissue under deficit irrigation compared with grafts without Paulsen interstock. This study suggests that using Paulsen as interstock, can be an adaptation strategy for water stress through controlling in some morphological, chemical physiological and anatomical responses of scion.

Postharvest quality and shelf life of Passiflora cincinnata BRS Sertão Forte fruits according to type of fertilization and storage

The present study aimed to evaluate the physicochemical characteristics and shelf life of P. cincinnata BRS Sertão Forte fruits produced with conventional fertilization recommended for passion fruit, conventional organic fertilization, organic fertilization enriched with biotite schist, conventional fertilization with replacement of the potassium source and chemical fertilization only and the mineral nutrition of plants stored under ambient and refrigerated conditions. Analyses of pH, soluble solids, titratable acidity, ratio, color, texture and mass loss were performed. Fertilizers differed in terms of nutrient absorption associated with protein synthesis (N, S, B, Cu, Mn, Zn), especially where soil remineralizer was applied. Treatments without fertilization and that with organic fertilization enriched with biotite schist soil remineralizer also positively influenced fruit physicochemical properties such as color and texture. Fruits stored under refrigeration conditions showed the best results for the conservation of their qualitative characteristics. Under the conditions of the present study, it could be concluded that the postharvest life of P. cincinnata fruits stored under refrigeration at 100C is at least 60 days. This period is 30 days under ambient conditions.

Mapping Apple Orchards in the municipality of São Joaquim (Santa Catarina, Brazil) using Sentinel-2 data

This study carried out a mapping procedure focusing on apple orchards considering the planted area, spatial location, altitude range, slope interval, and presence of anti-hail nets in the city of São Joaquim (Southern Santa Catarina Plateau, Brazil). Spectral images from the Sentinel-2 orbital platform acquired in August 2018 and an enhanced digital elevation model from the Shuttle Radar Topography Mission (SRTM) were used. In a GIS application configured with the SIRGAS 2000,4 reference system and UTM cartographic projection, Sentinel-2 constellation images and digital elevation models from the SRTM mission and more recently refined with sensor data Phased Array type L-band Synthetic Aperture Radar (PALSAR) were added. All images were resampled to a spatial resolution of 10m. The results were validated based on high spatial resolution images available from Google Earth. The results show that São Joaquim has a planted area of 7,974.80 ha, and only 12% use an anti-hail coverage system. The majority of the orchards range from one to five ha and belong to small producers. More than 50% of the orchards are between 1,200 and 1,400 m in altitude, with 45% of orchards located in areas with slopes between 8 to 20%. Interestingly, most of the orchards are concentrated in a radius of up to 20km from the urban center of São Joaquim, where industries and cooperatives are located for packaging, processing, and logistics. This study demonstrated that orbital data from Sentinel-2 can effectively quantify the distribution of apple orchards, being a viable and effective alternative for collecting information for agricultural monitoring. In this way, it enables efficient planning of apple production, such as technical assistance, marketing with producers, and production flow.

Sample size for postharvest quality traits of ‘Palmer’ mangoes

The objective of this study was to determine the most efficient sample size required to estimate the mean of postharvest quality traits of ‘Palmer’ mangoes harvested in two growing seasons. A total of 50 mangoes were harvested at maturity stage 2, in winter (June 2020) and spring (October 2020), and evaluated for weight, length, ventral and transverse diameter, skin and pulp L*, C* and hº, dry matter, firmness, soluble solids (SS), titratable acidity (TA) and the SS/TA ratio. According to the results, the coefficient of variation (CV) of fruit quality traits ranged from 2.1% to 18.1%. The highest CV in both harvests was observed for the SS/TA ratio, while the lowest was reported for pulp hº. In order to estimate the mean of physicochemical traits of ‘Palmer’ mangoes, 12 fruits are needed in the winter and 14 in the spring, considering an estimation error of 10% and a confidence interval of 95%. TA and the SS/TA ratio required the highest sample size, while L* and hº required the lowest sample size. In conclusion, the variability was different among physicochemical traits and seasons, implying that different sample sizes are required to estimate the mean of different quality traits in different growing seasons.

Characterization and molecular cloning of secreted α-amylase with dominant activity from mon thong durian (Durio zibethinus murr. cv. mon thong)

The secreted α-amylase with dominant activity was purified from the crude extract of Mon Thong durian by steps of ammonium sulphate precipitation and the affinity column chromatography. The purified α-amylase (DzAmy1) had a molecular mass of approximately 44 kDa. Its optimum pH and temperature for activity were 7.0 and 50°C, respectively. The enzyme was stable from pH 6 to 10 and from 30 to 60°C. Many metal ions did not affect amylase activity. The gene cloning of DzAmy1 was carried out and it was confirmed that DzAmy1 gene consisted of 1,254 bp open reading frame, which encoded 23 amino acids of the signal peptide and 395 amino acids of mature protein with a calculated molecular mass of 43.7 kDa. The isoelectric point of the enzyme was 5.78. DzAmy1 was shown to belong to sub-family one of the plant α-amylases based on phylogenetic tree analysis. Structural characterization by homology modelling suggested that it consisted of 3 domains with a catalytic triad in domain A. Recombinant DzAmy1 (rDzAmy1) was successfully expressed in Escherichia coli and had hydrolysis activity for starch and ethylidene-pNP-G7, which was clearly confirmed the authenticity of DzAmy1 as a functional α-amylase.

Genotypic selection of multispecific hybrids obtained through crosses between commercial Passiflora edulis and wild passiflora species

The interspecific introgression of resistance genes to diseases in commercial varieties through interspecific crosses has been adopted as a strategy in breeding programs of sour passion fruit. This work aimed to evaluate 11 progenies of multispecific hybrids obtained from crosses involving seven Passiflora species, in addition to four commercial cultivars, using the REML/BLUP method. The experiment was carried out as a randomized block design with six repetitions and three plants per plot. Ten fruit traits were evaluated. The additive, multiplicative, and sum of ranks indexes were applied to determine the most appropriate selective strategy in the simultaneous increase of fruit weight, number of fruits, and yield. Plants from the 325 x VAO progeny showed a lower bacterial defoliation index and better means predicted for the traits number of fruits and productivity. The progenies 325 x LD4, PL3 x LD4, and the controls CSB-Marília and BRS-Gigante Amarelo showed plants with better-predicted means for traits related to fruit quality. The genetic gains demonstrated good prospects for the use of wild species in sour passion fruit genetic breeding.

Assessment of economic and environmental performance in citrus-based intercropping systems

The economic and environmental performances of agriculture intercropping depend on the complementarities between the crops that make up the system. The objective of this work was to analyze the citrus-based intercropping systems in the Coastal Tablelands region of Northeastern Brazil, aiming to identify the associations of crops with better economic and environmental performances. The study started with the construction of a set of integrated indicators, with which the field information was recorded and the performance indices calculated, based on three principles: Profitability, Productive Efficiency, and Biological Regulation. Citrus orchards in monoculture resulted in lower environmental economic performance indices. The intercropping systems that yielded the best environmental and economic performance indices in the citrus orchards were: cassava; cassava, corn and beans; corn and pumpkin. The indicators associated with these economic-environmental performances were profit, seasonality, productive diversity, profit evenness, plant health control impact level, and efficiency in the use of water, nitrogen, and phosphate.

Identification of sources of resistance of Passiflora rootstocks to fusariosis in areas with disease outbreaks in Mato Grosso state, Brazil

The aim of the study was to identify sources of resistance of Passiflora rootstocks to Fusarium sp. in two experimental areas with histories of disease foci in Mato Grosso state, Brazil. The experiment was carried out from June 2012 to December 2015 and was of randomized block design with eight treatments in which susceptible cultivar P. edulis was grafted onto hybrids CPAC MJ-H-87, CPAC MJ-H-76, CPAC MJ-H-86 and CPAC MJ-H-88, the commercial cultivar and native P. edulis, P. nitida and P. alata. Mortality rates of grafted plants were evaluated up to 640 days after transplantation. All Fusarium sp. isolates were identified as F. oxysporum f. sp. passiflorae. Plant mortality occurred earlier in the clay area than in the area with sandy clay loam. Grafted plants involving P. edulis as rootstocks were highly susceptible to Fusarium sp. with overall mortality rates above 56.25% considering both soil types, while plants with CPAC MJ-H-76 or native P. nitida rootstocks were more resistant with mortality rates below 12.5%. Grafted plants with CPAC MJ-H-86 as rootstock were highly resistant in clay soil but highly susceptible in soil with high proportion of sand. Only grafted plants involving CPAC MJ-H-76 as rootstock showed moderate resistance.

Comparison of fruit maturation and quality of ‘Gala’ apple strains at harvest and after storage

Strains of ‘Gala’ apples with highly red-colored skins have been planted in new orchards based on consumer interest and financial returns to the producers. The effect of somatic mutation may not be limited to change in fruit skin appearance. In this study, six ‘Gala’ strains were compared regarding fruit maturity and quality attributes at commercial harvest time and after 210 days in controlled atmosphere cold storage plus seven days shelf-life. Experimental orchards were established in three regions and fruit assessed over four seasons. The fruit skin red color area was highest in ‘Baigent’ and ‘Galaxy’, and lowest in ‘Royal Gala’ and ‘Imperial Gala’. Fruit of ‘Maxi Gala’ and ‘Gala Real’ had intermediate skin coloration among the six strains. There was no difference among the strains regarding the fruit weight, starch index, flesh firmness, soluble solid content (SSC), and titratable acidity (TA) at harvest, and flesh firmness, SSC and TA after storage. Fruit of the six ‘Gala’ strains were equally affected by physiological disorders (flesh browning, fruit cracking, calcium deficiency disorders and shrivel) and fungal diseases (external decay, core rot and Glomerella cingulata spot) during storage, indicating that they have similar storability. Only ‘Imperial Gala’ and ‘Royal Gala’ exhibited superficial scald, an unusual disorder for ‘Gala’ cultivar. Harvest management and potential economic impacts of highly red colored fruit of ‘Gala’ strains are discussed.