Morphophysiological changes of Acca sellowiana (Myrtaceae: Myrtoideae) saplings under shade gradient

Understanding morphological and physiological changes under different light conditions in native fruit species in juveniles’ stage is important, as it indicate the appropriate environment to achieve vigorous saplings. We aimed to verify growth and morphophysiological changes under shade gradient in feijoa (Acca sellowiana (O. Berg) Burret) to achieve good quality saplings adequate to improve cultivation in orchards. The saplings were grown for twenty-one-month under four shading treatments (0%, 30%, 50%, and 80%). Growth, photosynthetic pigments, gas exchanges, chlorophyll fluorescence, and leaf anatomy parameters were evaluated. Saplings under full sun and 30% shade had higher height and diameter growth and dry mass accumulation due to higher photosynthesis rate. As main acclimatization mechanisms in feijoa saplings under 80% shade were developed larger leaf area, reduced leaf blade thickness, and enhanced quantum yield of photosystem II. Even so, the net CO2 assimilation and the electron transport rate was lower and, consequently, there was a restriction on the growth and dry mass in saplings under deep shade. Therefore, to obtain higher quality feijoa saplings, we recommend that it be carried out in full sun or up to 30% shade, to maximize the sapling vigor in nurseries and, later, this light environment can also be used in orchards for favor growth and fruit production.

Identification of plant genetic resources affected by shrimp farming in the southwestern coastal region of Bangladesh

The main purpose of the study was to identify the plant genetic resources (PGRs) affected by shrimp farming and to determine their magnitude of vulnerability. Data were collected from randomly selected 100 respondents, through personal interview, using an interview schedule, at Dumuria upazila of Khulna district, during 16 November 2009 to 15 February 2010. The fruit PGRs were more affected by shrimp farming than that of timber yielding and other types of PGRs. Among the 18-fruit PGRs available, all were endangered, except indigenous velvet apple, Diospyros peregrine (Gaertn.) Gürke, which was in threatened condition. Among the fruit species, banana, Musa acuminate; guava, Psidium guajava L.; jackfruit, Artocarpus heterophyllus Lam.; sapota, Manilkara zapota L. and betel nut, Areca catechu L. were in highly endangered. Among the 17-timber yielding and other plant species, only 7-PGRs were affected by shrimp farming while majority (10-PGRs) had been available in different extents. Among the vulnerable PGRs, bamboo, Bambusa bambos (L.) Voss; flame of the forest, Delonix regia (Boj. ex Hook.) Raf.; teak, Tectona grandis L.f. and banyan, Ficus benghalensis L. were endangered, while Indian ash tree, Lannea coromandelica (Houtt.) Merr.; ipil-ipil, Leucaena leucocephala (Lam.) de Wit and cool mat, Schumannianthus dichotomus (Roxb.) Gagnep. were in threatened condition. In general, the total fruit trees decreased in numbers (-74.17%) after inception of shrimp farming. On the other hand, the total numbers of timber yielding plants increased by 15.45%. From the overall consideration (irrespective of types), the number of plant population decreased (-58.10%) after inception of shrimp farming. It means that the plant species were affected by shrimp farming and became endangered. Int. J. Agril. Res. Innov. Tech. 11(2): 18-26, Dec 2021

SLOW GROWTH IN VITRO CULTURE FOR CONSERVATION OF HANCORNIA SPECIOSA GOMES

Hancornia speciosa Gomes is a fruit species endemic to the Cerrado and coastal plains of Northeast of Brazil, with great economic, nutritional, ecological, and medicinal potential. This study aimed to evaluate the effect of sorbitol and sucrose as osmotic regulators on the in vitro growth of mangabeira, aiming at conservation by slow growth. The explants were obtained from in vitro germinated seedlings and inoculated in MS medium supplemented with sucrose (15 and 30 g L-1) and sorbitol (0, 5, 10 and 15 g L-1). The experimental design was completely randomized with 20 repetitions in a 4 x 2 factorial arrangement (sorbitol x sucrose concentrations). The evaluations were performed at 30, 60 90 and 120 days of incubation. The analyzed variables were number of nodes/budding, number of leaves, leaf abscission, leaf color and survival of explants. The data were statistically analyzed by generalized linear model analysis. The results indicated a significant difference between the osmotic regulators and the culture time for all variables. Sorbitol showed a more pronounced growth-reducing effect than sucrose. The use of 30 g L-1 sucrose combined with 10 or 20 g L-1 sorbitol reduced the growth in a critical way, making it clear that the water stress caused was not tolerated by the plants, negatively interfering in its development. Treatment with 15 g L-1 sucrose combined with 5 g L-1 sorbitol promoted the best result, allowing the conservation of plants for 120 days.

Comparative Transcriptomic Analyses of Different Jujube Cultivars Reveal the Co-Regulation of Multiple Pathways during Fruit Cracking

Fruit cracking is a common physiological disorder in many fruit species. Jujube (Ziziphus jujuba Mill.) is an economically valuable fruit in which fruit cracking seriously affects fruit yield and quality and causes significant economic losses. To elucidate cracking-related molecular mechanisms, the cracking-susceptible cultivars ‘Cuizaohong’ and ‘Jinsixiaozao’ and the cracking-resistant cultivar ‘Muzao’ were selected, and comparative transcriptome analyses of cracking and non-cracking ‘Cuizaohong’ (CC and NC), cracking and non-cracking ‘Jinsixiaozao’ (CJ and NJ), and non-cracking ‘Muzao’ (NM) were conducted. A total of 131 differentially expressed genes (DEGs) were common to the CC vs. NC and CJ vs. NJ comparisons. To avoid passive processes after fruit cracking, we also mainly focused on the 225 gradually downregulated DEGs in the CJ, NJ, and NM samples. The functional annotation of the candidate DEGs revealed that 61 genes related to calcium, the cell wall, the cuticle structure, hormone metabolism, starch/sucrose metabolism, transcription factors, and water transport were highly expressed in cracking fruits. We propose that expression-level changes in these genes might increase the turgor pressure and weaken mechanical properties, ultimately leading to jujube fruit cracking. These results may serve as a rich genetic resource for future investigations on fruit cracking mechanisms in jujube and in other fruit species.

New host plant records.

New host plant records are presented for the following fruit species from Papua New Guinea, Indonesian Papua (West Papua, Central Papua, Papua), associated islands and Bougainville: Bactrocera neocheesmanae, B. bancroftii, B. contermina, B. frauenfeldi, B. musae, B. speculifera, B. trivialis and Dacus axanus.

Thinning as Method to Regulate Sweet Cherry Crops – a Review

In perennial fruit crops, bearing can be influenced by various factors, including environmental conditions, germplasm, rootstocks, and cultivation methods. Cherries, one of the most important and popular fruit species from the temperate climate zone, achieve high prices on the market. New agricultural technologies and environmental factors force a change in the approach to cherry cultivation. Old-type cherry orchards with their high demand for water, nutrients and manual work are replaced by orchards of self-pollinating cherry cultivars grown on dwarf rootstocks. These changes make it necessary to search for ways to regulate fruiting, in particular to thin buds, flower and fruit. In view of environmental regulations and consumer pressure, thinning methods are being sought that either do not involve the use of chemicals or that use eco-friendly chemical agents. This review examines recent progress in understanding the effect of thinning methods on the physiology, tree growth and fruit quality of cherries, discusses horticultural practices aimed to ensure regular cropping and their influence on fruit quality, and provides suggestions for future research.

Elucidation of Genetic Diversity as Morphological, Phytochemical and Molecular Markers in Some Hawthorn (Crataegus) Genotypes

Backround: Thanks to its ecological and geographical location, Turkey is the homeland of many fruit species and allows many fruit species to be grown. Hawthorn, which is understood to be important in human health and nutrition, is one of these fruit types. This study was carried out to identify morphological, biochemical and molecular genetic variations of 22 hawthorn genotypes belonging to three different species collected from Kayseri province. Methods and Results: Morphological, biochemical and molecular marker (ISSR) techniques were used to determine genetic diversity. The fruit and leaf characteristics of the genotypes showed differences. Among the biochemical properties of the genotypes, the antioxidant activity ranged from 23.13–61.59%, the total flavonoid content ranged from 16.63 to 57.22 mg QE/100 g, and the total phenolic content ranged from 277.28 to 310.80 mg GAE/100 g. Genotypes were compared with principal component analysis according to their morphological and biochemical characteristics. In the principal component analysis, species generally formed similar clusters. In molecular marker analysis, 101 bands were obtained from 13 ISSR primers. 76 of the bands are polymorphic and the polymorphism rate was calculated as 75.24%. The similarity index in the UPGMA dendogram obtained as a result of the molecular analysis ranged between 0.71 and 0.88. In the dendrogram, genotypes did not show a dense clustering by species. Conclusion The results obtained may benefit researchers in the determination and protection of gene sources in breeding studies on hawthorn species.

Genome-Wide Identification and Comparative Analysis of the ASR Gene Family in the Rosaceae and Expression Analysis of PbrASRs During Fruit Development

The members of the Abscisic Acid (ABA) Stress and Ripening gene family (ASR) encode a class of plant-specific proteins with ABA/WDS domains that play important roles in fruit ripening, abiotic stress tolerance and biotic stress resistance in plants. The ASR gene family has been widely investigated in the monocotyledons and dicotyledons. Although the genome sequence is already available for eight fruit species of the Rosaceae, there is far less information about the evolutionary characteristics and the function of the ASR genes in the Rosaceae than in other plant families. Twenty-seven ASR genes were identified from species in the Rosaceae and divided into four subfamilies (I, II, III, and IV) on the basis of structural characteristics and phylogenetic analysis. Purifying selection was the primary force for ASR family gene evolution in eight Rosaceae species. qPCR experiments showed that the expression pattern of PbrASR genes from Pyrus bretschneideri was organ-specific, being mainly expressed in flower, fruit, leaf, and root. During fruit development, the mRNA abundance levels of different PbrASR genes were either down- or up-regulated, and were also induced by exogenous ABA. Furthermore, subcellular localization results showed that PbrASR proteins were mainly located in the nucleus and cytoplasm. These results provide a theoretical foundation for investigation of the evolution, expression, and functions of the ASR gene family in commercial fruit species of the Rosaceae family.

Current Situation and Perspectives of Fruit Annonaceae in Mexico: Biological and Agronomic Importance and Bioactive Properties

The Annonaceae family is one of the oldest angiosperms. The genus Annona is the one with the most species and, together with Asimina, the only ones that contain edible fruits. In the last 10 years, interest in these fruit species has increased, mainly due to their nutritional properties and their application in the treatment of human diseases. Mexico is the center of origin for most of them. However, at present much of the basic agronomic information, postharvest handling of the fruits, and their potential as new crops for areas with poor soils in organic matter or semi-dry climates is unknown. It is considered that these custard apple species may be an option to change towards instead of crops that have lost profitability and sustainability. A review of the current state of knowledge in different areas of the species A. muricata, A. macroprophyllata, A. reticulata, A. squamosa, and A. cherimola was carried out and to focus research efforts on the topics of greatest interest and on those where is required to achieve a sustainable production and use of these resources in Mexico. However, knowledge about the cultivation and potential uses of these species is needed to increase their commercialization; the integration of interdisciplinary and interinstitutional groups is required.