Large Fruit Size Research Articles

Comprehensive agrobiological assessment and analysis of genetic relationships of promising walnut varieties of the Nikitsky Botanical Gardens.

Walnut is an important horticultural crop, the production of which ranks second among all nut crops. Despite the significant demand in the domestic market in Russia, the industrial production of walnut fruits in Russia is currently underdeveloped. At the same time, there is a need to update the assortment with new highly productive varieties adapted to local agro-climatic conditions and having high quality nuts that are competitive at the world level. An important issue for the successful implementation of breeding programs is a comprehensive study of the gene pool. In this regard, within the framework of the study, the task was to evaluate promising varieties from the collection of the walnut gene pool of the Nikitsky Botanical Gardens and analyze genetic relationships based on microsatellite genotyping. On the basis of the performed phenotypic assessment, the study sample, which included 31 varieties, was divided into several groups according to the main phenotypic traits, such as frost and drought resistance, the start of the growing season, the ripening period, the weight and type of flowering, the weight of the fruit, and the thickness of the endocarp. Varieties with economically valuable traits that can be recommended as promising as initial parental forms in breeding work for resistance to abiotic stress factors have been identified, as well as varieties with increased productivity and large fruit sizes. Based on the analysis of eight SSR markers (WGA001, WGA376, WGA069, WGA276, WGA009, WGA202, WGA089 and WGA054), an analysis of the level of genetic diversity was performed and genetic relationships were established in the studied sample of varieties. Six (for WGA089) to eleven (for WGA276) alleles per locus have been identified. A total of 70 alleles were identified for the eight DNA markers used, with an average value of 8.75. Analysis of SSR genotyping data using Bayesian analysis established the presence of two main groups of genotypes. Taking into account the fact that all the studied varieties are selections from local seed populations in different regions of the Crimean Peninsula, the revealed level of polymorphism may indirectly reflect the level of genetic diversity of the local walnut populations. Furthermore, the presence of two genetically distant groups indicates the presence of two independently formed pools of the autochthonous gene pool of the species Juglans regia L. on the Crimean Peninsula.

Fruit Quality and Metabolomic Analyses of Fresh Food Accessions Provide Insights into the Key Carbohydrate Metabolism in Blueberry.

Blueberry is a nutrient-rich berry, and its taste and flavor directly determine the consumer preference. Until now, few studies have focused on the comparison of fresh food quality and the key metabolites in superior fresh-eating blueberry cultivars. Herein, fruit quality indicators of 10 highbush blueberry cultivars were evaluated using 'Bluerain' as the control. Appearance quality analysis of fruits showed that 'Brigitta' had a larger fruit size and 'Anna' was the smallest. 'Anna' fruits, followed by 'O'Neal', had the highest ratio of soluble solids to acidity because of their lowest titratable acidity content. Despite the high soluble sugar content, the antioxidants in 'Anna' fruits such as total flavonoids, anthocyanins and vitamin C were lowest among all cultivars, while 'Duke' seemed to have opposite patterns. Furthermore, a total of 553 and 557 metabolites were identified by non-targeted metabolomics liquid chromatography-tandem mass spectrometry (LC-MS/MS) in positive and negative ion mode, respectively. Particularly, the numbers of differentially accumulated metabolites (DAMs) were the most between the 'O'Neal' vs. 'Bluerain' group. The DAMs involved in the metabolic pathways, sesquiterpenoid and triterpenoid biosynthesis, monoterpenoid biosynthesis, galactose metabolism, starch and sucrose metabolism, may be mainly related to the synthesis of flavor and carbohydrate substances. Moreover, the expression patterns of genes involved in sugar metabolism were verified by quantitative real-time PCR (qRT-PCR) analysis in different cultivars. Therefore, the systematical comparison of the quality characteristics, metabolites and expression profiles of related genes in highbush blueberries with good flavor could provide some basis for further research on fresh fruit breeding of blueberries.

Selection assessment of varieties and selected forms of black currant based on large fruit size

The article presents research findings on the weight of black currant berries. The research focused on the varieties and selected forms of black currant (Ribes nigrum L). Nara variety, adapted to local conditions, was used as a control. Studies were carried out in 2020–2022 at the plots for genetic collection and competitive trials of selected forms of black currants at the All-Russian Research Institute of Lupin (Bryansk region). The planting scheme involved a spacing of 3×0.8 m on grey forest soils. The observations were carried out using conventional methods. The varying weather conditions during the study period allowed for a more objective evaluation of the genotypes in terms of their adaptive capabilities and facilitated the selection of large-fruited and resistant forms. The most favourable meteorological conditions for berry weight development were observed in 2022. During this period, the average berry weight of the studied gene pool was 2.5 g. Among the examined varieties, Dobrynya (3.5 g), Debryansk (2.7 g), Chara (2.6 g) and Selechenskaya 2 (2.6 g) demonstrated the largest berry sizes with variation coefficients of 20%, 28%, 7%, and 17%, respectively. Large-fruited forms having an average berry weight exceeding 3 g and high stability (V=3%) were selected from the hybrid family 6-12- 224×6-26-207 – 7-3-227 (3.6 g), 7-3-213 (3.4 g), 7-19-100 (3.6 g) and Selechenskaya 2×Treasure – 6-20-67 (3.5 g). These genotypes represent valuable parent material for further breeding aimed at increasing berry weight. New large-fruited sources with a combination of important breeding traits (large fruit, high vitamin C content, resistance to powdery mildew and bud mite), namely,7-19-100, 7-3-227, 7-18-250, 7-13-232 and 7-17-150, were identified. The variety Dessert Olkhina exhibited the smallest berries (0.8 g) with a variability of 20%. The influence of weather conditions on the weight of berries was established, revealing a positive average correlation between berry weight and precipitation levels from May to July (r=0.52) and the hydrothermal index of the growing season (r=0.56).

Africa as an evolutionary arena for large fruits.

Strong paleoclimatic change and few Late Quaternary megafauna extinctions make mainland Africa unique among continents. Here, we hypothesize that, compared with elsewhere, these conditions created the ecological opportunity for the macroevolution and geographic distribution of large fruits. We assembled global phylogenetic, distribution and fruit size data for palms (Arecaceae), a pantropical, vertebrate-dispersed family with > 2600 species, and integrated these with data on extinction-driven body size reduction in mammalian frugivore assemblages since the Late Quaternary. We applied evolutionary trait, linear and null models to identify the selective pressures that have shaped fruit sizes. We show that African palm lineages have evolved towards larger fruit sizes and exhibited faster trait evolutionary rates than lineages elsewhere. Furthermore, the global distribution of the largest palm fruits across species assemblages was explained by occurrence in Africa, especially under low canopies, and extant megafauna, but not by mammalian downsizing. These patterns strongly deviated from expectations under a null model of stochastic (Brownian motion) evolution. Our results suggest that Africa provided a distinct evolutionary arena for palm fruit size evolution. We argue that megafaunal abundance and the expansion of savanna habitat since the Miocene provided selective advantages for the persistence of African plants with large fruits.

The Pollen Donor Affects Seed Development, Taste, and Flavor Quality in 'Hayward' Kiwifruit.

To investigate how different species or ploidy level of pollen donors affects the fruit quality of kiwifruit, flowers of 'Hayward' kiwifruit (a hexaploid Actinidia deliciosa cultivar, 6x) were hand-pollinated with pollen from ten different male donors. Kiwifruit plants pollinated with four distant species-M7 (2x, A. kolomikta), M8 (4x, A. arguta), M9 (4x, A. melanandra), and M10 (2x, A. eriantha)-had a low fruit-setting rate and therefore were not investigated further. Of the other six treatments, kiwifruit plants pollinated with M4 (4x, A. chinensis), M5 (6x, A. deliciosa) M6 (6x, A. deliciosa) had a larger fruit size and weight than those pollinated with M1 (2x, A. chinensis) and M2 (2x, A. chinensis). However, pollination with M1 (2x) and M2 (2x) resulted in seedless fruits, having few small and aborted seeds. Notably, these seedless fruits had higher fructose, glucose, and total sugar and lower citric acid content. This resulted in a higher sugar to acid ratio compared to fruits from plants pollinated with M3 (4x, A. chinensis), M4 (4x), M5 (6x), and M6 (6x). Most volatile compounds increased in the M1 (2x)- and M2 (2x)-pollinated fruit. A combination of principal component analysis (PCA), electronic tongue, and electronic nose suggested that the different pollen donors significantly affected the kiwifruit's overall taste and volatiles. Specifically, two diploid donors had the most positive contribution. This was in agreement with the findings from the sensory evaluation. In conclusion, the present study showed that the pollen donor affected the seed development, taste, and flavor quality of 'Hayward' kiwifruit. This provides useful information for improving the fruit quality and breeding of seedless kiwifruit.

Pomological evaluation and GT-biplot analysis of promising open-pollinated genotypes of apricot (Prunus armeniaca L.)

Apricot is an important stone fruit species with different cultivars cultivated worldwide. Therefore, breeding programs are necessary for developing new varieties with various fruit quality and sensory traits. The present study evaluated morphological and fruit-quality attributes of thirty-seven apricot genotypes selected from several Iranian and Italian open-pollinated cultivars together with Shahroudi cultivar (control) during two growing seasons (2019–2020) using the UPOV descriptor and GT-biplot analysis. The results showed great variability in fruit size among all apricot genotypes studied. Most genotypes showed medium-sized fruits while large and small fruits were observed in eight and four genotypes, respectively. The highest yield was recorded in G-464, G-432, G-588, Shahroudi and G-571. Genotypes G-432, G-464, G-571, G-573, and G-576 had higher fruit weight than Shahroudi. In addition, G-450 and G-553 had the highest TSS (18.2°Brix) and TSS/TA (25.4), respectively. The GT-biplot analysis revealed that fruit weight and dimensions along with pH and TSS could be indicators for selecting superior genotypes. According to the present study, G-464, G-571 and G-450 can be introduced as superior genotypes and it is expected that the inter-crossing of these three have the potential to produce cultivars with sweet fruit, high yield and large fruit size.

Internal Flesh Browning in Apple and Its Predisposing Factors—A Review

This review article is focused on internal flesh browning (IFB)-related physiological disorders affecting apple (Malus domestica Borkh.) fruit. The expression of different physiological and metabolic IFB-related disorders during post-harvest storage are investigated along with the pre-harvest factors contributing to development. The effectiveness of commercially available pre-harvest technologies for preventing IFB-related disorders are also examined. Internal flesh browning-related disorders are erratic and devastating disorders that result in post-harvest deterioration of fruit quality in apples. Internal flesh browning-related disorders can result in severe economic losses to the apple industry through reduced consumer trust and market acceptability of susceptible cultivars. There are several IFB-related disorders and incidence can range from 0 to 100% of a crop, with severity ranging from no brown flesh to browning of the entire fruit flesh. While IFB-related disorders are found in several apple cultivars, some cultivars are more prone than others. The development of IFB-related disorders involve complex mechanisms depending upon the different types and causes, or factors involved in loss of structural integrity and functional stability of the cell membranes and cell components. Membrane disruption followed by enzymatic oxidation of fruit phenolic compounds by polyphenol oxidases and the production of brown polymers is considered to be the general underlying mechanism causing the browning of flesh tissue. It can be observed in different patterns based on the injured portion of the fruit flesh and the cause of membrane disruption. Three broad categories of IFB-related disorders, including chilling injury, internal CO2 injury, and senescent-related browning disorders, are discussed along with their sub-types. The development of IFB-related disorders can be influenced by both pre-harvest factors and post-harvest conditions and their interactions. Although commonly associated with storage, IFB can also be found immediately after harvest and sometimes in unharvested fruit prior to full maturity. As pre-harvest conditions are a strong contributor to IFB-related disorders, the influence of several pre-harvest orchard conditions, including fruit size, crop load, maturity at harvest, cultivar, climatic conditions, seasonal temperatures, growing degree days, and major mineral nutrients, such as nitrogen (N), phosphorus (P), potassium (K), and calcium (Ca) are reported. Although there are contradictory findings in the studies reported, in general, factors such as larger fruit size, light crop load and delayed harvesting, along with cool temperatures after bloom and warmer temperatures before harvest, increase the risk of IFB-related disorders. In relation to fruit mineral concentrations, high N and low Ca have been associated with increasing IFB, while there is conflicting evidence in relation to the impact of both P and K. This review also examines the effectiveness of commercial pre-harvest technologies such as 1-methylcyclopropene, aminoethoxyvinylglycine and diphenylamine in the prevention of IFB-related disorders, but none of these technologies were found promising due to varied and contradictory results.

Flowering type and morphological diversity of Bido coconut from Morotai Island District, Indonesia

Abstract. Mawardi S, Romadhon MR, Rahma, Maskromo I, Dinarti D, Sudarsono. 2023. Flowering type and morphological diversity of Bido coconut from Morotai Island District, Indonesia. Biodiversitas 24: 1473-1481. In general, coconuts are divided into Tall and Dwarf types. Dwarf coconut is early bearing and has a short trunk, while Tall coconut yields high-quality copra and has a large fruit size. Furthermore, Bido-Tall coconut is an early bearing with a short trunk, medium size fruit, and high-quality copra. This research aims to evaluate Bido coconut population variations and study the flowering types of Bido and other coconut types in the research locations. Morphological and flowering type observation was conducted for Bido Tall, Local Tall, Local Dwarf, and Bido Tall outcrossing progenies at Bido Village, North Maluku, Indonesia. Flowering-type observations were carried out on three successive inflorescences. The Bido Tall, Dwarf, and the Bido Tall outcrossing progenies exhibited natural autogamy pollination, while the Local Tall coconut was semi-autogamy. The Principal Component Analysis (PCA) results indicated that the stem girth at 20 cm and 150 cm above ground, the internode length, the leaf numbers, the fruit color, and the fruit numbers cumulatively contributed to 68.80% of the observed coconut variabilities. Most Bido Tall coconut individuals were clustered separately from the existing local Tall and Dwarf coconuts. However, the clustering analysis showed average similarity among Bido Tall, the Local Tall, and Dwarf coconuts are still above 70%. The similarity coefficient among the Bido Tall coconut, the Bido Tall outcrossing progenies (natural hybrids), and the Local Tall was higher than among Bido Tall to the Local Dwarf coconuts.

Genetic Variability of Different Jordanian Almond Prunus Amygdalus L. Landraces Revealed by Morphological Traits and RAPD Markers

The relationship among six Jordanian almond landraces was studied using morphological traits and RAPD analyses. Across six almond landraces studied, nut shape, kernel size, nut length, nut size, and shell length That showed a high level of variation (CV>30%), while kernel length, shell width, internodes length, and nut width showed comparatively low values (CV<20%). Principal component analysis showed that the first five components explained all morphological variation among the landraces investigated. Kernel and nut traits were predominant in the first three components contributing to most of the total variation that existed among landraces. Euclidean distance was used to construct clusters from morphological data which allocated individuals into two main groups with a distance ranging from 5.5 to 10.14. Hajari, Hami Hallo, and Mukhmaly with small fruit sizes composed one main cluster, while the other three landraces (Oga, Fark, and Abu Dabos) with large fruit sizes composed the other main cluster. Out of 62 pre-screened RAPD primers, 12 with reproducible bands and maximum polymorphism were selected for diversity analysis. Seventy-one bands were scored with 28 of them being the polymorphic. Average value of polymorphism/primer ranged from 20% to 74.2%. Nei's genetic distance coefficient ranged from 0.5 to 0.85 with an average of 0.70. Molecular analysis revealed inconsistent separation among the landraces compared with that based on morphological traits. Although landraces found during the screening in the Ajloun area are limited in number, but considerable variation was observed both at morphological and DNA levels indicating that Jordanian almond landraces are rich and valuable genetic materials for almond improvement.

Reproductive functional organization of woody plant assemblages along regeneration in a Caatinga dry forest

Tropical forest regeneration across old fields has been mainly described as a predictable sequence of functional plant assemblages in response to environmental filtering. However, the way plant reproductive diversity is organized along forest regeneration and how the reproductive profile of woody flora may impact regeneration have been poorly investigated. This paper examines the organization of plant assemblages throughout the regeneration of a Caatinga dry forest in the context of slash-and-burn agriculture with a focus on reproductive plant traits and strategies. We hypothesized a recovery and directional changes in specialist reproductive traits/strategies along forest regeneration but with aridity and chronic anthropogenic disturbances posing contrary forces to this recovery process. This study was carried out in a human-modified landscape of Caatinga dry forest in northeast Brazil. We compiled information on woody plant assemblages inhabiting a forest chronosequence consisting of 28 forest stands of varying age: 14 regenerating (4–50-yr old) and 14 old-growth forests. Woody plant assemblages along forest regeneration had higher occurrence of specialized traits and strategies, such as pollination by vertebrates (16.6%) and dispersion by animals (47.8%). Regenerating forest stands exhibited a higher occurrence of species with specialized floral size (19%) and pollination by vertebrates (26.5%) as compared to old-growth forests. Regenerating forest stands also supported a higher (30%) functional diversity of reproductive traits than old-growth stands. Biomass, aridity, and chronic anthropogenic disturbances affected a myriad of traits/strategies: pollination by birds and animal dispersion increased with increases in biomass while total functional diversity responded negatively; pollination by Sphingids and beetles negatively responded to aridity, while very large fruit size species negatively responded to chronic anthropogenic disturbances. Both forest biomass and aridity correlated negatively with reproductive trait diversity. The Caatinga dry forest regeneration suggests high resilience, no directional/predictable changes (although regenerating vs. old-growth differ in some traits) and aridity imposed to the successional mosaics as a driver. This pattern probably emerges conditioned by the reproductive traits posed by the plant species able to thrive in such stressful environments, including those species that persist through the entire regeneration process, i.e., the regeneration process is marked by high complexity and low predictive power. Although rapid recovery represents good news, the plant-assemblage reproductive profile imposed by disturbance-adapted species may drastically alter resource availability for a myriad of plant attendants (e.g., pollinators and thief) and, consequently, the complex/diverse plant-animal interactions typical of dry forests. This working hypothesis has both theoretical and applied implications in the context of dry forest regeneration in human-modified landscapes.

Identification of Genetic Markers and Genes Putatively Involved in Determining Olive Fruit Weight.

The fruit size of a cultivated olive tree is consistently larger than its corresponding wild relatives because fruit size is one of the main traits associated with olive tree domestication. Additionally, large fruit size is one of the main objectives of modern olive breeding programs. However, as the long juvenile period is one main hindrance in classic breeding approaches, obtaining genetic markers associated with this trait is a highly desirable tool. For this reason, GWAS analysis of both genetic markers and the genes associated with fruit size determination, measured as fruit weight, was herein carried out in 50 genotypes, of which 40 corresponded to cultivated and 10 to wild olive trees. As a result, 113 genetic markers were identified, which showed a very high statistically significant correlation with fruit weight variability, p < 10−10. These genetic markers corresponded to 39 clusters of genes in linkage disequilibrium. The analysis of a segregating progeny of the cross of “Frantoio” and “Picual” cultivars allowed us to confirm 10 of the 18 analyzed clusters. The annotation of the genes in each cluster and the expression pattern of the samples taken throughout fruit development by RNAseq enabled us to suggest that some studied genes are involved in olive fruit weight determination.

Quercusmangdenensis, a new species of Quercus (Fagaceae) from Kon Tum Province, Vietnam.

Quercusmangdenensis Binh & Ngoc, sp. nov. (Fagaceae) is newly described from Mang Den Town in the central highland of Vietnam. The new species is characterized by lanceolate to oblong-lanceolate leaves with entire margin, 1-5-fruited infructescence, larger fruit size 6-10.5 cm long, broadly bowl-shaped cupules enclosing 1/5 of the nut, bracts of cupule entire and arranged in 5-7 rings, and cylindrical-ellipsoid and basally flat nuts 4.5-7.5 cm long. Quercusmangdenensis is morphologically similar to Q.bidoupensis Binh & Ngoc and Q.kontumensis A.Camus in having similar leaf shape, cuneate leaf base, and bracts arrangement in cupules. However, it differs from Q.bidoupensis and Q.kontumensis by cupules broadly bowl-shaped, much larger fruits, cylindrical-ellipsoid nut shape, and cupule enclosing 1/5 of the nuts. A description, photographs, and preliminary species conservation status of the new species are also provided.

Quality attributes of garden strawberry fruits and breeding for their improvement

Based on the analysis of domestic and foreign literary sources the information about the main quality attributes of garden strawberry fruits (large fruit size, hardness or firmness of fruits, biochemical composition) and breeding possibilities of their improvement at the present stage of breeding is summarized. Quality characteristics of garden strawberries are differentiated by groups: commercial, consumer, biochemical, physical and mechanical, technological. When growing garden strawberries for fresh consumption, the following large-fruited varieties were identified: Clery (Italy), Florence (UK), Alba (Italy), Roxana (Italy), Vima Xima (Netherlands), Vima Tarda (Netherlands), Vima Kimberly (Netherlands), Maya (Italy), San Andreas (USA), Taira, Nelly, Kemiya, Elegy, Alpha, Bereginya, Tsaritsa, Krymchanka 87, Arossa, Zarya, Krymskaya rannaya, Uniol, Jantarnaja. The trait of fruit hardness refers to the technological characteristics, but it also depends on the appearance of fruits during harvesting and transportation, which determines the commercial appearance. The following varieties have a high degree of fruit hardness: Tsaritsa, Surprise olympics, Rubinovy kulon, Feyerverk, Aquarelle, Alina, Nelli, Induka (Netherlands), Clery, Darselect (France), Tenira (Netherlands), Selekta (Canada), Polka (Netherlands), Irma (Italy), Alba, Asia (Italy), Syria (Italy), Onda (Italy), Vivaldi (Netherlands). Strawberry fruits are characterized by a unique composition of biologically active compounds that determine the nutritional value of the crop as a source of dietary and therapeutic and preventive nutrition. Studies indicate a predominant role of genotype in the accumulation of antioxidants in garden strawberry fruits, as well as the influence of growing conditions on the realization of the genetic potential of the varieties. Due to the development of cultivation technologies and the expansion of knowledge about the nutraceutical value of garden strawberries, improving the quality of fruits has become one of the priority objectives of breeding programs around the world. To increase the level of fruit quality traits in garden strawberry, the greatest effect can be achieved by using the original forms with proven donor properties on these traits in breeding.

Invasive Drosophila suzukii outnumbers native controphics and causes substantial damage to fruits of forest plants

Impacts of biological invasions are diverse and can have far-reaching consequences for ecosystems. The spotted wing drosophila, Drosophila suzukii, is a major invasive pest of fruits, which negatively affects fruit and wine production. However, little is known about the ecological impact of this fly species on more natural ecosystems it has invaded, such as forests. In this study, we investigated the use of potential host plants by D. suzukii at 64 sites in different forest communities in Switzerland from mid-June to mid-October 2020. We examined more than 12,000 fruits for egg deposits of D. suzukii to assess its direct impact on the plants. We recorded symptoms of fruit decay after egg deposition to determine if D. suzukii attacks trigger fruit decay. In addition, we monitored the drosophilid fauna with cup traps baited with apple cider vinegar, as we expected that D. suzukii would outnumber and potentially outcompete native controphics, especially other drosophilids. Egg deposits of D. suzukii were found on the fruits of 31 of the 39 potential host plant species studied, with 18 species showing an attack rate &amp;gt; 50%. Overall, fruits of Cotoneaster divaricatus (96%), Atropa bella-donna (91%), Rubus fruticosus corylifolius aggr. (91%), Frangula alnus (85%) and Sambucus nigra (83%) were attacked particularly frequently, resulting also in high predicted attack probabilities that varied among forest communities. Later and longer fruiting, black fruit colour, larger fruit size and higher pulp pH all positively affected attack rates. More than 50% of the plant species showed severe symptoms of decay after egg deposition, with higher pulp sugar content leading to more severe symptoms. The high fruit attack rate observed was reflected in a high abundance and dominance of D. suzukii in trap catches, independent of forest community and elevation. Drosophila suzukii was by far the most abundant species, accounting for 86% (81,395 individuals) of all drosophilids. The abundance of D. suzukii was negatively associated with the abundance of the native drosophilids. Our results indicate that the invasive D. suzukii competes strongly with other frugivorous species and that its presence might have far-reaching ecosystem-level consequences. The rapid decay of fruits attacked by D. suzukii leads to a loss of resources and may disrupt seed-dispersal mutualisms through the reduced consumption of fruits by dispersers such as birds.

EVALUATION OF ADVANCED TOMATO MUTANTS BASED ON GROWTH, YIELD ATTRIBUTES AND YIELD

Field experiment was conducted during November 2009 to March 2010, to investigate growth and yield attributes of advanced tomato mutants (TM-110 and TM-219) along with three cultivars (BARI tomato-3, BARI tomato-14 and BINA tomato-5) following randomized complete block design with three replications. There were significant genotypic differences in respect of morpho-physiological characters (plant height, branch and leaf area, total dry mass, absolute growth rate and relative growth rate), biochemical parameter (nitrate reductase), reproductive characters (number of effective and non-effective flower cluster, number of flowers and reproductive efficiency), phenological characters (days to flowering start, days to first harvest and harvesting duration), yield attributes and fruit yield. In general high yielding genotypes showed superior performance in plant height, branch number, leaf area, total dry mass production, absolute growth rate, nitrate reductase activity and fruit size compared to low yielding ones. Relative growth rate,chlorophyll, photosynthesis, reproductive characters and fruit number had no relationship with fruit yield in tomato. The variety BARI tomato-14 showed the highest fruit yield (77.7 t ha-1) due to its superiority in respect of morpho-physiological, biochemical and larger fruit sizes. In contrast, the mutant TM-110 and the variety BINA tomato-5 produced the lower fruit yield (average 51.2 t ha -1) due to poor performance in growth characters and smaller size of fruits. However, TM-110 matured 4-15 days earlier than the other mutant/varieties. Further, harvesting duration was higher in high yielding genotypes than low yielding ones. The highest harvesting duration was recorded in BARI tomato-14 (28 days) followed by BARI tomato-3 (26 days). This information may be implicated in future plant breeding programme.

​Effect of Foliar Applied Nitrogen with Growth Regulators (2,4 D, GA3, Amrut-pani) and Soil Applied Potassium on the Management of the Rough-skin Disorder of Nagpur Mandarin (Citrus reticulata Blanco)

Background: Rough-skin disorder mainly occurs in 6-12 years old young and senile orchards of Nagpur mandarin due to excess application or availability of potassium. The characteristics of rough-skinned fruits are large fruit size with rough textured peel, segments are loose intact with rind, improper fruit shape (fruit length to breadth ratio is equal to one or more than one), reduced juice per cent and TSS. Methods: Based on the incidence of rough-skin disorder, an orchard of Nagpur mandarin was earmarked at Hetikundi village of Wardha district, Maharashtra for Mrig bahar during 2020. The selected orchards are 10 years old, spaced at 6 m x 6 m and grafted on Rangpur lime rootstock. At harvest, yield and yield attributes, fruit physical characteristics and critical quality characteristics viz. TSS, acidity, TSS/ acidity ratio and vitamin C content of disordered and normal fruits were recorded according to treatments. Result: Foliar application of plant growth regulators like 2,4-D 15 ppm and GA3 15 ppm and reducing soil application of potassium in high potassium available soils reduced the rough skin and improved the rind texture and physicochemical characteristics at harvesting in mrig bahar.

Improvement of recombinant miraculin production in transgenic tomato by crossbreeding-based genetic background modification.

An important optimization step in plant-based recombinant protein production systems is the selection of an appropriate cultivar after a potential host has been determined. Previously, we have shown that transgenic tomatoes of the variety 'Micro-Tom' accumulate incredibly high levels of miraculin (MIR) due to the introduction of MIR gene controlled by a CaMV35S promoter and a heat-shock protein terminator. However, 'Micro-Tom' is unsuitable for commercial production of MIR as it is a dwarf cultivar characterized by small-sized fruit and poor yield. Here, we used the crossbreeding approach to transfer the high MIR accumulation trait of transgenic 'Micro-Tom' tomatoes to 'Natsunokoma' and 'Aichi First', two commercial cultivars producing medium and large fruit sizes, respectively. Fruits of the resultant crossbred lines were larger (~ 95 times), but their miraculin accumulation levels (~ 1,062μg/g fresh mass) were comparable to the donor cultivar, indicating that the high miraculin accumulation trait was preserved regardless of fruit size or cultivar. Further, the transferred trait resulted in a 3-4fold increase in overall miraculin production than that of the previously reported line 5B. These findings demonstrate the effectiveness of crossbreeding in improving MIR production in tomatoes and could pave the way for a more efficient production of recombinant proteins in other plants.

Pewarisan Karakter Kuantitatif Persilangan Tanaman Melon

One of the efforts to solve the problem of limited quality melon seeds is to assemble melon varieties with distinctive fruit characters in terms of shape, taste, and color of the flesh. In general, farmers choose meon seeds that have a sweet taste, flesh color, large fruit size, and have a long shelf life . Analysis of quantitative character inheritance is very important in plant breeding programs. This analysis is used to obtain genetic information consisting of the number of genes controlling the character, gene action, genetic diversity, heritability and other genetic information. This study aims to study the inheritance pattern of several quantitative characters in melon crosses. The research design was a randomized block design with eight genotypes as treatment. The results showed that there was a maternal effect on the two crosses of melon plants G1 ((PK-669 x D-612) and G3 ((PK-361 x PK-165) on the characters of fruit diameter, fruit length, fruit weight, and leaf area. Heritability values in a broad sense on all parameters ranged from 0.95-1.00.

Vegetative and generative properties of two apple cultivars ‘Galiwa’ and ‘Story Inored’ in a multi-row system

In a five-year (2015-2019) study, some vegetative and generative peculiarities of two resistant apple cultivars (‘Galiwa’ and ‘Story Inored’) were assessed in a young orchard with a multi-row training system. Based on our research, cv. ‘Galiwa’ showed significantly weaker growth, than cv. ‘Story Inored’, which was manifested in lower trunk cross sectional area (TCSA) and lower tree height. Cultivar ‘Story Inored’ reached the optimal tree height (3.1 m) at the age of four, but cv. ‘Galiwa’ could not achieve it neither in five-year-old trees (2.7 m). Cultivar ‘Galiwa’ showed 28.4-32.6 t/ha calculated average yield, while cv. ‘Story Inored’ produced 41.3-102.7 t/ha. Larger fruit size was found in cv. ‘Galiwa’ (72.7-79.1 mm) and smaller in cv. ‘Story Inored’ (66.9-69.2 mm). The fruit surface color was under 50% for cv. ‘Galiwa’ (43-49%), meanwhile cv. ‘Story Inored’ reached higher coloration (87-93%) and an excellent color intensity (4.8-5.0). Shape of cv. ‘Galiwa’ fruits was rather flat, than globular (0.83-0.84 shape index), as cv. ‘Story Inored’ was more elongated (0.95-1.00 shape index).

An impact assessment of alien invasive plants in South Africa generally dispersed by native avian species

Invasive alien plant species have been identified as a major threat to biodiversity and the relationship with native avian dispersers may increase their invasion potential. The impact of invasive plant species needs to be quantified using comparable assessment tools across different habitats and species to allocate limited resources to high-priority species. Here, we used the Generic Impact Scoring System (GISS) to assess the impacts of 16 fleshy-fruited alien invasive plant species in South Africa generally dispersed by native avian species. The results showed that fleshy-fruited invasive species have both environmental and socio-economic impacts. The cumulated impact scores for lantana (Lantana camara) and the tree of heaven (Ailanthus altissima) were the highest, with scores of 42 and 32, respectively. Some species, such as white mulberry (Morus alba), camphor tree (Cinnamomum camphora), American bramble (Rubus cuneifolius) and Brazilian pepper tree (Schinus terebinthifolius), had low overall impact scores of 8, 18, 14 and 16, respectively, but scored the maximum impact of 5 for certain mechanisms. Environmental impacts of fleshy-fruited invasive plant species had a high impact magnitude through effects on the ecosystem and vegetation. Socio-economic impacts were mainly through effects on forest production, agriculture and human health. Species with large crop sizes, small seeds and fruit sizes had higher environmental and socio-economic impact magnitude. The information generated in this study is important for guiding resource allocation and preventing the uncontrolled introduction of invasive species in South Africa. The impact of the fleshy-fruited invasive species transcended sectors and, therefore, effective management of invasive species will require the collaboration of multiple and inter-sectoral stakeholders in South Africa.