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The sustained higher profitability of a pomegranate orchard relies heavily on the production of a greater proportion of high-quality fruits, a goal achievable through the implementation of effective management practices. The objective of this study is to provide site-specific supplementary knowledge regarding the response of pomegranate plants to various management practices under arid conditions. With the aim of enhancing both marketable fruit yield and quality of pomegranate in arid regions, four separate and simultaneous experiments were conducted in the same orchard to evaluate (i) the response of planting materials derived from tissue culture, air layering, and cutting; (ii) the impact of crop (fruit) load; (iii) the response of crop regulation; and (iv) the application response of organo-mineral fertilizers containing potassium (OMF-K) and phosphorus (OMF-P). The results obtained for plant growth, fruit yield, and fruit quality did not exhibit significant differences among pomegranate plants raised through the three different methods of vegetative propagation. Striking results in terms of producing superior-grade fruits, higher marketable yield, and overall fruit quality were achieved with crop loads of 80 fruits per plant. Staggering the crop regulation from June to September effectively extended the harvesting season to four months, from the last week of November to March, with eventual benefit of reduced fruit cracking compared to the standard two-month harvesting period obtained from normal regulation. Soil application of the indigenously developed OMF-K in two equal splits, along with the recommended N and P through inorganic sources, significantly reduced fruit cracking (only 6.23%) compared to the recommended NPK through inorganic sources (26.9%), while maintaining similar physicochemical quality attributes.

Water scarcity and climate variability impede the realization of satisfactory vegetable yields in arid regions. It is imperative to delve into high-productivity and water-use-efficient protected cultivation systems for the sustained supply of vegetables in harsh arid climates. A strenuous effort was made to find suitable protected structures and levels of irrigation for greenhouse cucumber production in hot arid zones of India. In this endeavor, the effects of three low-tech passively ventilated protected structures, i.e., naturally ventilated polyhouse (NVP), insect-proof screenhouse (IPS) and shade screenhouse (SHS), as well as three levels of irrigation (100%, 80% and 60% of evapotranspiration, ET) were assessed for different morpho-physiological, yield and quality traits of the cucumber in a two-year study. Among the low-tech protected structures, NVP was found superior to IPS and SHS for cucumber performance, as evidenced by distinctly higher fruit yields (i.e., 31% and 121%, respectively) arising as a result of higher fruit number/plants and mean fruit weights under NVP. The fruit yield decreased in response to the degree of water shortage in deficit irrigation across all protected structures. However, the interaction effect of the protected structure and irrigation regime reveals that plants grown under moderate deficit (MD, 20% deficit) inside NVP could provide higher yields than those obtained under well-watered (WW, 100% of ET) conditions inside IPS or SHS. Plant growth indices such as vine length, node number/plant, and shoot dry mass were also measured higher under NVP. The greater performance of cucumber under NVP was attributed to a better plant physiological status (i.e., higher photosystem II efficiency, leaf relative water content and lower leaf water potential). The water deficit increased water productivity progressively with its severity; it remained higher in NVP, as reflected by 20% and 94% higher water productivity than those recorded in IPS and SHS, respectively, across different irrigation levels. With the exception of total soluble solids and fruit dry matter content (which were recorded higher), fruit quality parameters were reduced under water deficit conditions. The findings of this study emphasize the importance of considering suitable low-tech protected structures (i.e., NVP) and irrigation levels (i.e., normal rates for higher yields and moderate deficit (−20%) for satisfactory yields) for cucumber in hot arid regions. The results provide valuable insights for growers as well as researchers aiming to increase vegetable production under harsh climates and the water-limiting conditions of arid regions.

Pomegranate (Punica granatum L.) is a fruit tree that is globally distributed, especially in warm areas with low annual rainfall and limited water availability. This species exemplifies the critical role of water in agriculture and the need for efficient irrigation practices due to its characteristics, cultivation requirements, and geographic diffusion. In this study, we investigated the effects of drip irrigation and mulching on the vegetative growth, yield, and fruit quality attributes of pomegranate. The experiment involved three irrigation regimes (100% of evapotranspiration, 80%, and 60%) and three mulching treatments (no mulch, plastic mulch, and organic mulch) in a factorial combination. Both irrigation and mulching had significant positive influences on the yield and fruit quality attributes. Specifically, deficit irrigation strategies showed a negative impact on the fruit yield per tree, with a greater effect observed as the severity of the irrigation deficit increased. Mulching, on the other hand, led to a significant increase in the fruit yield, primarily attributed to an increase in fruit size. Furthermore, the analysis indicated that irrigation and mulching treatments had distinct effects on fruit traits such as the fruit length, width, volume, and rind thickness. Interestingly, the study highlighted that the effects of irrigation and mulching on fruit quality attributes were mostly independent of each other, suggesting an additive influence rather than an interaction between the two factors. These findings underscore the importance of considering irrigation and mulching practices for optimizing fruit quality in pomegranate cultivation, particularly in semi-arid regions. The results contribute valuable insights for farmers and researchers seeking to enhance fruit production and quality.

An experiment was conducted on the effect of pre-harvest spray of calcium chloride (1–2%), pre-cooling, packaging materials and storage conditions on shelf life and quality of lasora fruits. The LDPE bags were found most efficient in reducing the PLW followed by cling film and brown paper bags both under ambient and refrigerated conditions. The pre-cooled fruits revealed significantly lower PLW compared to non pre-cooled fruits up to 4th day in ambient condition and till 14th day in refrigerated conditions. Under ambient conditions, the maximum shelf life of 7 days was recorded in LDPE followed by cling film wrap and brown paper bags while under refrigerated conditions it could be extended up to 14 days in LDPE and cling film packed fruits and 7 days in brown paper. The spoilage was significantly higher at ambient condition within 7 days in LDPE packed fruits (3.54%) and least in cling film. The spoilage increased to 10–12% in refrigerator when the fruits were stored for longer duration and it was not affected significantly by different treatments. The antioxidant activity was absent in the fruits stored in ambient condition while it was recorded in refrigerated fruits even after 14 days of storage.

Jujube or ber (Ziziphus spp.) is one of the most important fruit crops of India’s arid and semi-arid regions because of its high adaptability to resource constraints hot (semi)arid region. Jujube is a rich source of minerals, vitamins and dietary antioxidants to arid zone dwellers, where it is known as poor man’s apple. Given the present rising trends in discovering and exploiting plant-based health-promoting compounds, it is imperative to know the extent of variability with respect to fruit nutritional compositions present in the jujube germplasms. In this study, we assessed genetic variability for fruit nutritional and functional quality traits in eighteen jujube accessions belonging to three species (Z. mauritiana, Z. rotundifolia and Z. oenoplia) from an ex-situ collection from Indian arid and semi-arid regions in two consecutive fruiting seasons (2020-21 and 2021-22). Results revealed significant variability among eighteen jujube genotypes for important fruits physico-biochemical parameters. The IC 625864 (Z. oenoplia) identified as a superior accession for fruit antioxidant potential with having high levels of total phenols (256.2 mg/100 g dry weight) and total antioxidants (423 mg/100 g in FRAP). Moreover, IC 625849 (Z. mauritiana) and IC 625848 (Z. rotundifolia) were other genotypes containing high levels of phenols and total antioxidant (FRAP). Thus, while aiming for simultaneous improvement for total antioxidants with phenols, IC 625848, IC 625849 and IC 625864 genotypes can be considered as valuable resource for jujube fruit quality improvement program. Further, the high levels of phenotypic variance with high genotypic variance coupled with high heritability and genetic advance particularly for total antioxidants, total phenols, and ascorbic acid contents in fruits, indicating them to be considered as reliable biochemical markers to identify the productive genotypes having higher amounts of dietary antioxidants. Depending on the identified genotypes for their richness in the particular phytonutrients, these can be exploited either for table purpose or biofortification of other products, or using in jujube breeding program for quality improvement.

Pomegranate (Punica granatum, L.) is a fruit tree that is increasingly popular worldwide due to the health-related properties of the fruit juice. While several studies highlighted the rich phytochemical diversity, few efforts have been devoted to an integrative understanding of the level of diversity of this species. This study investigated the diversity of 40 pomegranate accessions in an Indian ex situ collection by using twenty-nine morphological traits, six biochemical parameters, and twenty-nine Simple Sequence Repeats (SSR) markers. Among the evaluated traits, fruit volume (23.34% CV), fruit weight (21.12% CV), and fruit color (*a) (22.69 % CV) largely contributed to the morphological classification. Based on Mahalanobis D2 distance and Tocher’s clustering, the 40 pomegranate accessions were grouped into eight clusters, partly consistent with their origin. Specifically, cultivars introduced from foreign countries were present in distinct clusters. The SSR marker analysis generated 66 alleles. The observed heterozygosity values ranged from 0.05 to 0.63, with a mean value of 0.30. Maximum molecular genetic dissimilarity was observed between ‘IC-318720′ and ‘Gul-e-Shah Red’ (0.30). The neighbor-joining dendrogram separated wild accessions from cultivated varieties. The combination of morphological, biochemical, and molecular characterization allowed for comprehensively characterizing the pomegranate diversity and provided information on the relationships between the different aspects of the diversity. This work also suggests that the origin of the accessions is an important factor of discrimination and that the level of admixture between local and foreign material is currently limited.

The Japanese plum (Prunus salicina Lindl.) is a fruit tree globally cultivated in temperate regions of the world. Its floral biology and yield are affected by several factors, with issues related to self- and cross- (in) compatibility among varieties being emblematic of the whole Rosaceae family. The aim of this work was to elucidate the fruit set, dynamics of pollen tube growth in pistil, and yield and other fruiting attributes, in ‘Satluj Purple’ and ‘Kala Amritsari’, probably the most popular subtropical Japanese plum varieties in northern regions of India. Specifically, we examined the response of six different pollination variants, namely to self-pollination, open-pollination with the two cultivars located in adjacent rows, open-pollination with the two cultivars located in distant rows, manual cross-pollination, supplementary pollination, and floral bouquet. During the two years of the investigation, both plum cultivars showed good in vitro pollen germination (on average, above 50%) at different sucrose concentrations, with the highest values for the ‘Satluj Purple’ and for the 15% concentration. In vivo, the analysis of the pollen growth in the various sections of the style indicated the best performance when pistils of ‘Satluj Purple’ were pollinated by pollen grains of cv. ‘Kala Amritsari’. Cross-pollination also registered faster growth of pollen tube in pistil with the lowest number of incompatible pollen tubes compared to open- and self-pollination. From the productive point of view, cross-pollination showed the most pronounced results among the different pollination variants, with the highest initial fruit set (36.6%) and yield (28.0 kg/tree), and the shorter fruit development in ‘Satluj Purple’ (fruit set and yield in self-pollinated ‘Satluj Purple’ trees were 3.3% and 2.0 kg/tree, respectively). Conversely, the use of ‘Satluj Purple’ pollen for ‘Kala Amritsari’ showed poor results. Finally, in our study, ‘Kala Amritsari’ showed self-compatibility. We conclude that the main cause of poor fruit set in ‘Satluj Purple’ is self-incompatibility. The relevant genotypic-specific effects revealed by the analysis of the various pollination treatments also highlighted the importance of interplanting to increase fruit set and yield for subtropical Japanese plum varieties.

Protected cultivation is gaining momentum in (semi) arid regions to ameliorate the adverse environmental impacts on vegetable crops, besides ensuring high resource use efficiency in resource-limiting environments. Among the less techno-intensive protected cultivation structures, naturally ventilated polyhouses (NVP), insect-proof net houses (IPN) and shade net houses (SNH) are commercial structures in India. With the aim to find the best-protected structure, together with optimum irrigation level, for high yield and water productivity of the tomato crop, the most popular crop in hot arid regions, we evaluated tomato performance in low-tech protected structures (NVP, IPN and SNH) in interaction with three irrigation levels (100, 80 and 60% of crop evapotranspiration, ETc) during spring–summer of 2019 and 2020. The NVP was found superior to both the net house structures (IPN and SNH) for different performance indicators of tomatoes under investigation. The components of plant growth (leaf and stem dry mass) and fruit yield (fruit size, weight, yield), as well as fruit quality (total soluble solids, fruit dry matter and lycopene content) were higher in NVP, regardless of irrigation level. The yield as well as water productivity were significantly higher in NVP at 100% ETc. However, there was no statistical variation for water productivity between NVP and IPN. Microclimate parameters (temperature, relative humidity and photosynthetic active radiation) were markedly more congenial for tomato cultivation in NVP followed by IPN in relation to SNH. Consequently, plants’ physiological functioning with higher leaf relative water content (RWC) and lower leaf water potential concomitantly with better photosynthetic efficiency (chlorophyll fluorescence, Fv/Fm), was in NVP and IPN. Most growth and yield attributes were depressed with the decrease in water application rates; hence, deficit irrigation in these low-tech protected structures is not feasible. For tomato cultivation in resource-scarce arid regions, the combination of the normal rate of irrigation (100% ETc) and NVP was optimal for gaining high yield as well as water productivity as compared to net houses.

Nematodes are a serious problem across pomegranate-growing areas worldwide, but the severity is higher in light sandy soils of arid regions. The present study was carried out to explore the integrated approaches for the control of nematodes in pomegranate. Three different experiments were carried out during 2017–2020 to (a) delineate nematode abundance in major pomegranate areas, (b) screen pomegranate genotypes against nematode, and (c) assess the efficacy of integrated management for the control of root knot nematode in pomegranate. The survey results revealed that none of the pomegranate orchards were found to be free from nematode infestation. Moreover, the majority of the orchards (78%) showed moderate incidence (10.1 to 40%) of infestation. A significant yield reduction (40.2%) and a decrease in fruit size was observed in nematode-affected trees. Pattern of cuticular markings in the perineal area of the mature female confirmed the occurrence of Meloidogyne incognita only in all the surveyed orchard of pomegranate. All the evaluated genotypes and varieties were found susceptible to root knot nematodes, but the severity of the attack varied among them. Hence, more detailed screening is needed on a larger population. Nematode population (number of galls g−1 root) can be minimized significantly with the combined applications of Carbofuran at 20 g + Fluensulfone at 20 g per plant or Neemcake 500 g + Paecilomyceslilacinus at 25 mL + Carbofuran at 20 g + Fluensulfone at 20 g per plant in April and August.

Nowadays, there is a large demand for nutrient-dense fruits to promote nutritional and metabolic human health. The production of commercial fruit crops is becoming progressively input-dependent to cope with the losses caused by biotic and abiotic stresses. A wide variety of underutilized crops, which are neither commercially cultivated nor traded on a large scale, are mainly grown, commercialized and consumed locally. These underutilized fruits have many advantages in terms of ease to grow, hardiness and resilience to climate changes compared to the major commercially grown crops. In addition, they are exceptionally rich in important phytochemicals and have medicinal value. Hence, their consumption may help to meet the nutritional needs of rural populations, such as those living in fragile arid and semi-arid regions around the world. In addition, local people are well aware of the nutritional and medicinal properties of these crops. Therefore, emphasis must be given to the rigorous study of the conservation and the nutritional characterization of these crops so that the future food basket may be widened for enhancing its functional and nutritional values. In this review, we described the ethnobotany, medicinal and nutritional values, biodiversity conservation and utilization strategies of 19 climate-resilient important, underutilized fruit crops of arid and semi-arid regions (Indian jujube, Indian gooseberry, lasora, bael, kair, karonda, tamarind, wood apple, custard apple, jamun, jharber, mahua, pilu, khejri, mulberry, chironji, manila tamarind, timroo, khirni).

Red-fleshed dragon fruit offers an array of bioactive compounds. Its cultivation is gaining momentum in India, including in arid and semi-arid conditions. Among various factors, the fruit developmental stages and climatic conditions of locations greatly influence the biosynthesis and actual contents of different bioactive compounds and mineral contents of the fruit. The changes in physical attributes, and bioactive and mineral content in red-fleshed dragon fruit grown in semi-arid conditions in India were assessed and quantified at six developmental stages. Significant changes occurred in the physical attributes of the fruit and the bioactive compounds and mineral content during the fruit maturation stages of the red-fleshed dragon fruit. The fruit physical characteristics, such as fruit size, fruit and pulp weight gain, peel thickness, and fruit firmness, along with eating quality parameters, such as soluble solids, sugars, acidity and soluble proteins, were observed at optimum at 35 days after anthesis (DAA). The decrease in total phenolics (29.96%), total flavonoids (41.06%), and vitamin C (75.3%) occurred throughout the fruit development stages, whereas the content of betalains, which was detected initially at 25 DAA, increased (48.6%) with the progression of the fruit development stages. However, the antioxidant capacity and free radical scavenging activity demonstrated variable trends throughout the fruit maturation period. There was an increasing trend in all the minerals up to 35 days, followed by a slight decrease, except for phosphorus content, which increased until the last stage of evaluation. The colour characteristics, in conjunction with the bioactive and antioxidant potential determined in the present study, suggest that red-fleshed dragon fruit can be harvested at 35 DAA for long-distance transportation, and from 35 to 40 DAA for local marketing.

The bioactive compounds, total antioxidant activity and minerals in white, pink and red flesh guava (Psidium guajava L.) varieties were assessed and quantified at three different stages of maturity in arid conditions. Changes in pectin content followed similar trend as fruit firmness and it gradually decreased till ripe stage. Total soluble solids and total sugars increased till full ripe stage but reverse was case for acidity. Ascorbic acid in white flesh guava varieties increased till colour turning stage and then after it decreased, while in coloured varieties it showed decreasing trend till ripe stage. White flesh varieties contains negligible quantity of anthocyanin, lycopene and total carotenoid while pink flesh (Lalit) had highest concentration of these compound followed by red flesh (Red flesh). Total phenols and total antioxidant activities of guava fruits were comparatively low during green mature stage and it increased progressively in later stages. Flesh colour did not show any definite pattern on phenolic content and total antioxidant activities. Phenols was recorded highest in Allahabad Safeda, while total antioxidant activities in Lalit. Stage of maturation showed variable changes in mineral contents in guava varieties. It can be inferred from the present study that the remarkable metabolic changes occur between mature green to colour turning stage.