Fruit Set Stage Research Articles

Simulation of pepper (Capsicum annuum L.) growth stages under different nitrogen fertiliser levels based on three models

ABSTRACT The pepper variety ‘Sanying’ was treated with different nitrogen levels (0.36, 0.72, 1.08, 1.44, 1.80, 2.16, 2.52, 2.88 g/basin) in 2022. The onset, end dates, and the meteorological data of the environment of each growth period were recorded. Simulation models of the effect of nitrogen levels on the growth period of pepper were constructed with physiological development time (PDT), product of thermal effectiveness and photosynthetically active radiation (PAR) (TEP), and growing degree days (GDD) as indices using experimental data from March to September. The models were fitted and verified with experimental data from April to October. The results showed that with the increase of the amount of nitrogen fertiliser, the growth process of pepper showed a significantly delayed trend. The root mean squared errors of the fitting values and observed values during the flowering stage, fruit setting stage, and harvesting stage of peppers were 1.02 days, 1.05 days, and 1.27 days, respectively. The relative errors were 0.71%, 0.88%, and 0.95%, and the coefficients of determination (R 2) were 0.97, 0.96, and 0.94, respectively. Therefore, the PDT model is the optimal model with the highest simulation accuracy to simulate the pepper phenological stage under different nitrogen levels.

Alkane biosynthesis is promoted in methyl jasmonate-treated sweet cherry (Prunus avium) fruit cuticles.

The cuticle plays an important role in the survival of plants, and it is important to preserve the quality of fleshy fruits like sweet cherry. Plant hormones play a role in cuticle formation. In this sense, jasmonates have been shown to induce cuticle biosynthesis, but until today this has not been demonstrated in sweet cherry fruit. Therefore, the effect of exogenous methyl jasmonate (MeJA) application at the fruit set stage on the expression levels of cuticle synthesis-related genes and the wax composition of the isolated cuticle was studied in developing and ripe fruits of sweet cherry (Prunus avium 'Bing'), respectively. MeJA treatment resulted in up-regulation of the cuticle biosynthesis-related gene expression, such as PaWINA, PaWINB, PaKCS1, PaKCS6, PaLACS1, PaLACS2, PaWS, and PaWBC11. These genes play a vital role in the elongation and transport of fatty acids, and wax biosynthesis. Analysis of cuticular components in ripe fruit showed an increase in long-chain linear aliphatic wax compounds, particularly C27, C28, C29, C30, and C31 alkanes. Exogenous MeJA application at the fruit set stage of sweet cherry has a significant effect on the wax composition of the ripe fruit cuticle, particularly in terms of alkane biosynthesis. The results of this study may provide insights into the regulation of cuticle biosynthesis by jasmonates and be useful for improving fruit quality and storage life. © 2023 Society of Chemical Industry.

Studies on the Effect of Split Application of NPK fertilizers on Growth and Yield of Papaya under Central Dry Zone of Karnataka

A field experiment was conducted at Eswargere village, Hiriyur taluk, Chitradurga district during the year 2020-2021 to assess the effects of split application of nitrogen, phosphorus, and potassium (NPK) fertilizer on papaya growth and yield, and the experiment was set up in Randomized Complete Block Design. The treatments include seven treatments comprising varying rates (75, 100 and 125% recommended dose of fertilizers) and time of application (Bimonthly and monthly intervals). Among growth attributes plant height (186.70 cm), stem girth (46.38) was recorded highest in 125% RDF through split application. In yield attributes maximum fruit length (23.54 cm) circumference (44.75 cm), volume (1711.07 cc) firmness (7.43 kg/cm2), total yield (138.83 t/ha) and lowest cavity index (14.84) were also observed in 125% RDF through split. Applying of 125% RDF through split at different growth stages (187.5:156.25:125 N: P2O5: K2O g/plant) in vegetative stage of 4 months, (62.5:125:187.5 N: P2O5: K2O g/plant) in flowering to fruit set stage of 2 months, (62.5:31.25:312.5 N: P2O5: K2O g/plant) in fruit development stage of 3 months at monthly interval showed to be better for fetching maximum plant growth and yield of papaya fruits.

Eggplant-garlic intercrops reduce the density of Tetranychus urticae on eggplant and improve crop yield.

Diversification of cultivation systems plays a critical role in ecosystem functions such as pest control, diversity of beneficial arthropods, and soil fertility. Repellent plants (releasing volatile organic compounds as arthropod repellents and providing alternative prey for natural enemies) may be used in an intercropping system for pest control; however, little is known concerning their relative priority. In this study, the impact of intercropping eggplant (E) (Solanum melongena L.) and garlic (G) (Allium sativum L.) in three designs -with row ratios of 4E:4G, 4E:8G, or 4E:12G -was assessed on the density of the two-spotted spider mite (TSSM) (Tetranychus urticae Koch), the abundance and diversity of predators, and crop yields, compared with the sole crops over two growing seasons of 2019 and 2020. In three intercrops, a significant decrease in the density of TSSM egg and mobile stages was observed compared with the sole eggplant at each growth stage of eggplant. The damage index by TSSM on eggplants was lower in intercrops (8.1-11.5%) compared with sole crop (37.0-40.3%) in the two seasons. The abundance of Stethorus gilvifrons was lower in the three intercrops than in the sole crop on the blooming-initial fruit set and the fruit development stages of eggplant. The density of Orius niger was higher in the three intercrops compared with the sole crop on vegetative growth and flowering to initial fruit set stages of eggplants. The abundance of Chrysoperla carnea was not significant among treatments. Greater values of the Shannon diversity index and the Pielou's evenness index for the construction of TSSM predators were recorded in the three intercrops compared with the sole eggplant over both growing seasons. In addition, a significant improvement in the yield per unit area of eggplant and garlic was obtained in intercrops compared with sole crops. These results indicate intercropping eggplant and garlic was a practical solution for reducing TSSM on eggplant, promoting the abundance of predators, and improving the crop yields of eggplant and garlic compared with the sole crops.

Tracking the Variations in Trace Elements, Some Nutrients, Phenolics, and Anthocyanins in Grewia asiatica L. (Phalsa) at Different Fruit Development Stages.

Grewia asiatica L. (phalsa) is a very prevalent berry in Pakistan and is consumed extensively asraw or in the form of juice. Here, for the first time, we assessedphalsa from Pakistan in terms of variations in macro and micro minerals, nutrients,and bio-active phyto-constituents including total phenolic and anthocyanin contentsat different fruit developmental stages. It was found that the sugars in phalsa increased from D1 (small at the initial fruit setting stage) to D6 developmentstage (fully ripened fruit) where sugars at D5 (near to fully ripe) and D6 stages were many times greater than at D1, D2 (unripe close to full-size completion), D3 (close to semi ripe), and D4 stage (semi ripened and full-size attainment). Total acidity of was declined in all developmental stages, where the D1 stage displayed maximum and D6 with the lowest acidity. Ascorbic acid was decreased from D1 to D2 and then increased graduallyfrom D3 to D5 stages. At the D6 stage, againa steep decline in ascorbic acid was observed. The total phenolics (mg gallic acid equivalents/100g) at stage D6 were higher (136.02 ± 1.17), whereas D1 being the lowermost in totalphenolic content (79.89 ± 1.72). For anthocyanins (mg/100g), an increasing pattern of changes was observed in all stages of phalsa fruit where the D1 stage showed lower (13.97 ± 4.84) anthocyanin contents which then increased gradually at stage D2 (67.79 ± 6.73), but increased sharply at D3 (199.66 ± 4.90), D4 (211.02 ± 18.85), D5 (328.41 ±14.96) and D6 (532.30 ± 8.51) stages. A total of four anthocyanins such as cyanidin, delphidine-3-glucoside, pelargonidin, and malvidin in phalsa were identified using HPLC procedures, and a significant > 90 % DPPH inhibition in phalsa was observed at the D5 and D6 developmentstages. The macro and micro minerals includingNi, Zn, Fe, Ca, Cu, Mg, Na, P, and K contents were decreased from initial (D1) stage tothe final (D6)development stage, while only Fe displayed an increasing trend from the initial to final fruit development stages (D1-D6). Conclusively, these findings could be of greatinterest for patients who are intended to consume phalsa as adjuvant therapy against diabetes and metabolic syndromes and other diseases involving reactive oxygen species with minimum metal toxicity.

Effect of Plant Growth Regulators on Growth, Yield and Quality of Papaya cv. Red Lady under Prayagraj Agro Climatic Conditions

The present investigation was conducted on 1-month-old seedlings from March 2022 to Jan 2023 to find out the suitable treatment for growth, yield and quality of Papaya cv. Red Lady. The statistical design adopted for the experiment was randomized block design (RBD) with three replications and ten treatment combinations. viz, T0 (Control), T1(NAA 100 ppm), T2 ( NAA 150 ppm), T3 (NAA 200 ppm), T4 (GA3 100 ppm), T5 (GA3 150 ppm), T6 (GA3 200 ppm), T7 (CCC 500 ppm), T8 (CCC 750 ppm), T9 (CCC 1000 ppm). The treatments were applied by soil drenching at the initiation of the experiment, vegetative phase, pre-flowering and fruit setting stage to assess the effect on growth, yield and quality of papaya. The results of the present investigation revealed that the treatment T6 (GA3 200 ppm) outstand in all the aspects like maximum plant height (142.13 cm), number of functional leaves per plant (17.14), stem diameter (54.37 mm) minimum days to first flowering (95.42), no. of flowers per plant (56.09), no. of fruit per plant (23.12), fruit weight (1263.38 gm), fruit yield/plant (29.22 kg), yield (129.85 t/ha­-1), fruit length (20.49 cm), fruit diameter (18.21 cm) and quality parameters like maximum TSS (16.61 ºBrix) and acidity (0.125 %), non-reducing sugar (2.16 ºBrix), reducing sugar (7.83 ºBrix), total sugar (9.99 ºBrix) followed by T5 (GA3 150 ppm). The lowest observation was recorded in T0 (Control). Treatment with GA­3, NAA and CCC improved vegetative growth, yield and quality to a lesser extent as compared to the control. That’s why a positive response has to be seen in particular treatment during the research trial.

Avian Feeding Guilds in Winter and Rainy Crop Seasons of Guava

A comparative study was conducted on avian feeding guilds in winter and rainy crop seasons of guava at Punjab Agricultural University campus, Ludhiana, Punjab, during 2021-22. A total of 53 bird species belonging to 46 genera, 31 families and 13 orders were noted during the study period. The recorded bird species were classified into six feeding guilds. Except for insectivore, carnivore and omnivore birds, 13 species were recorded to play no beneficial role in the combined data of winter and rainy crop seasons. Relative abundance of insectivore bird species was found to be 40.34% at flowering stage, 25.44% at fruit set stage and 13.92% at fruit ripening stage in winter crop season; 35.43% at flowering stage, 26.35% at fruit set stage and 14.21% at fruit ripening stage in rainy crop season. Major feeding groups of omnivore and frugivore species were noted during the fruit ripening stage of both seasons. During rainy crop season, nine bird species were observed feeding on insects. A statistical analysis of avian feeding guilds using the T-test revealed a significant difference in flowering and fruit ripening stages of guava crop seasons in the winter and rainy seasons.

Effect of Calcium Nitrate and Calcium Carbonate on Plant Growth, Fruit Quality and Yield of Papaya Cv. Red Lady

A field experiment was performed to study the effects of foliar applications of CaCO3 and Ca(NO3)2 on growth, quality, yield, and shelf life of papaya (Carica papaya) Cv. Red lady. Calcium (Ca) is one of the major plant nutrients which affects significantly the formation of the cell walls and cell membranes and also enables the production of biomass with proper plant growth and function. In the current experiment, papaya seedlings were well established in the orchard, well-irrigated with standardized nutrient solutions with all required inter-culture activities. Four different pre-harvest foliar application sprays were provided with two varying sources of Ca (CaCO3 and Ca(NO3)2) at three concentrations of each with CaCO3 (2%, 1%, 0.5%) Ca(NO3)2 (2%, 3%, 4%) at different stages of growth like flowering stage, fruit set stage, pre-harvest stage. The study revealed that foliar spray of above mentioned concentrations showed a profound improvement in vegetative growth of plants in terms of their height and diameter as compared to the plants in control treatment and also affected the fruit quality of papaya fruit.

Canonical correlation analysis applied to regulated deficit irrigation in ‘Tommy Atkins’ mango trees

The objective was to identify the effect of regulated deficit irrigation on physiological, yield and root descriptors of ‘Tommy Atkins’ mango tree grown in a semi-arid region of Brazil. The work was carried out during two production cycles on an 11-year-old mango orchard. The design was randomized blocks with five treatments and six replications. Irrigation treatments were based on the trees’ development stage: T1, irrigation supplying 100% of the crop evapotranspiration (ETc) in three production stages: fruit set stage (SI), fruit expansion stage (SII), and physiological maturation stage of the fruits (SIII); T2, 50% ETc in SI and 100% ETc in SII and SIII; T3, 100% ETc in SI and SIII and 50% ETc in SII; T4, 100% ETc in SI and SII, and 50% ETc in SIII; and T5, without irrigation in all three stages. Physiological data were measured once per stage. After harvesting the second cycle, roots were collected, following a completely randomized design, with five treatments and three replications, to determine the total root length density. Total or partial water deficit in ‘Tommy Atkins’ mango trees was identified by decreasing transpiration (E) and photosynthesis (A) and increasing leaf temperature (Tleaf). The total root length density is similar in all irrigation strategies up to 1 m horizontal distance and 0.10 m depth. Water deficit applied in the physiological maturation stage improves yield and water use efficiency.

Calcium foliar fertilization and its effect on quality and shelf life in andean blackberry fruits (Rubus glaucus Benth.)

Calcium is the third most crucial nutrient for andean blackberry; however, its absorption is limited in acid soils, and its low mobility in the plant decreases its effects on fruits. Therefore, the effect of foliar fertilizers with calcium on andean blackberry fruits was estimated. In three locations, experiments were established with five calcium sources (Ca chelate, CaB nitrate, Ca oxide, CaB and CaBZn gluconate) and a control without calcium, applied in three phenological stages and recording: weight, diameters, firmness, color, juice, pulp, pH, soluble solids, acidity, dehydration, and damage. Soil and tissue analysis was performed to identify the relationship between the plant’s nutritional conditions and its fertilization response. For the statistical analysis were used mixed models, tests of means, and principal components. Foliar fertilization with chelate, nitrate, and calcium oxide in andean blackberry crops with thorns, in production, with pruning management, and in the phenological stages of flower bud, fruit set, and red fruit, is a viable alternative to improve firmness, weight, and diameter of the fruits. In contrast, the chemical and color parameters in andean blackberry fruits depend on the edaphoclimatic conditions of each zone. This fertilization should be considered as a complement in soils without acidity problems and with balanced cationic saturations.

Influence of Different Levels of NAA and 2, 4, 5-T on Fruit Drop, Fruiting, Fruit Retention, Growth and Yield of Indian Ber (Zizyphus mauritiana Lamk.)

The experiment was carried out at Horticulture Garden, Department of Fruit Science, Chandra Shekhar Azad University of Agriculture & Technology, Kanpur (U.P.) during the November 2020- March 2021 and November 2021- March 2022. Sixteen treatments viz. four levels of NAA (0, 20, 30 and 40 ppm) and 2,4,5-T (0, 10, 20 and 30ppm) were studies in a Factorial Completely Randomized Design with three replications. Spraying was done on eleventh November, 2020 in first year and fifteenth November, 2021 in second year at fruit setting stage (Pea Stage) with fine nozzle sprayer in each treatment to give uniform spray on all over the treatment of ber plant. Application of (NAA@40 ppm and 2,4,5-T@30 ppm) significantly maximized initial fruit set (162.00 and 163.66), maximum fruit retention (20.39 and 20.43 percent) and maximum initial fruit set percentage (79.60 and 79.56 per cent). The length and width of fruit was significantly (5.35 and 4.99 cm) and (4.24 and 4.27 cm) respectively increased by application same concentration mention above. The maximum (36.62 and 36.82 g) fruit weight and physical properties of fruits like volume (36.57 and 36.42 cc) recorded under treatment (NAA@40ppm and 2,4,5-T@30ppm). The minimum stone length (0.88 and 0.87 cm), minimum stone diameter (0.88 and 0.87 cm), minimum stone weight (0.65 and 0.66 gm) and specific gravity (0.94 and 0.94 g cc-1) significantly found under (NAA@40 ppm and 2,4,5-T@30 ppm). The yield of ber was significantly increased (39.53 and 40.49) kg per plant, yield per hectare (121.30 and 121.33quintal) with treatment combination (NAA@40ppm and 2,4,5-T@30ppm) both the years of experiment.

Response of Brinjal (Solanum melongena L.) to Bio-stimulants in Relation to Growth, Yield and Quality

Field experiment was conducted during December 2018 to April 2019 at the Student’s farm, Department of Agriculture Science & Rural Development, Loyola Academy degree and pg college, Secunderabad to find out the effect of bio-stimulants on growth and yield of Brinjal var. Utkarsha. The experiment was laid out in Randomized Block Design (RBD) and the treatments comprised of: T1- Folicist @ 3 ml l-1, T2 – Fylloton @ 3 ml l-1, T3 – Globalga @ 3 ml l-1, T4 – Tata Bahar @ 2.5 ml l-1, T5 – Neo-Alpha @ 2.5 ml l-1, T6 – Daiwik @ 2.5 ml l-1, T7 – Recommended dose of NPK alone and T8 – control. Biostimulants were applied as foliar spray at pre-flowering, flowering and fruit setting stages. From the results of the experiment, it was observed that all the growth parameters i.e., plant height (92 cm), number of branches (12 plant-1) and number of leaves (38 plant-1) were significantly increased by the application of folicist @ 3.0 ml l-1 and it was at par with tata bahar @ 2.5 ml l-1. Same treatment also resulted significant increase in terms of number of flowers (68 plant-1), number of fruits (29 plant-1). The fruit length (7.8 cm), fruit diameter (8.35 cm), average fruit weight (90 g fruit-1), fruit yield (2.55 kg plant-1) were recorded in foliar application of folicist @ 3 ml l-1 and it was onpar with foliar application of tata bahar 2.5 ml l-1. The lowest values of growth parameters, yield attributes and yield were observed in control (T8). From the present study it can be concluded that application of folicist @ 3.0 ml l-1 will fetch the remuneration to the farmers.

Effect of Bio-stimulants on Growth, Development and Yield of Chilli (Capsicum annum L.)

A field experiment was conducted during December 2018 to April 2019 at the Student’s farm, Department of Agriculture Science & Rural Development, Loyola Academy, Secunderabad to know the effect of bio-stimulants on growth and yield of Chilli. The experiment was laid out in Randomised Block Design (RBD) and the treatments comprised of: T1- Folicist @ 3 ml/L, T2 – Fylloton @ 3 ml/L, T3 – Globalga @ 3 ml/L, T4 – Tata Bahar @ 2.5 ml/L, T5 – Neo-Alpha @ 2.5 ml/L, T6 – Daiwik @ 2.5 ml/L, T7 – Recommended dose of NPK, T8 – Control. Biostimulants were applied as foliar spray at pre-flowering, flowering and fruit setting stages. From the results of the experiment, it was observed that all the growth parameters i.e., plant height (85 and 82 cm), no. of branches (29 and 26) and number of leaves/plant (288 and 262) were significantly increased by the application of Folicist @ 3.0 ml/L and Tata Bahar @ 2.5 ml/L compared to other treatments and control (54 cm, 13 and 150). Same treatment application resulted in significant increase interms of no. of flowers/plant (78 and 75), number of fruits/plant (128 and 124) and % fruit set (80.5 and 78.2%). The highest number of fruits/ plant, average fruit weight (110.5 and 105.6 g/ 10 fruits), yield/plant (682 g) were recorded in foliar application of Folicist @ 3 ml/L closely followed by Tata Bahar (674 g) and Daiwik (650 g) and the lowest values were observed in control (410 g). Application of biostimulants significantly increased the vitamin-C content of fruits compared to control.

Physiological changes of sweet pepper under low irrigation regimes applied in three phenological stages of vegetative growth, reproductive growth, and fruit set

ABSTRACT A factorial experiment based on a completely randomised design (CRD) with 10 replicates was planned to evaluate if commercially low irrigation reduced output and how physiologically low irrigation influenced yield at different plant growth stages. In three phonological phases of the vegetative stage (VG), reproductive stage (RP), and fruit set (FS), two irrigation regimes of 100% of field capacity (FC) and 80% field capacity (low irrigation = LI) were employed. The results demonstrated that the shoot's fresh weight did not vary between the VG and RP phases, but rose during the FC stage. In FS, both photosynthesis and transpiration were reduced. VG had the highest amounts of photosynthesis and transpiration. Nevertheless, fruit yield rose during the second and third weeks of FS. As starch dropped and glucose, sucrose, and fructose increased, plasma membrane aquaporins (PIP) gene expression and abscisic acid (ABA) levels climbed. In conclusion, it was proved that lowering water consumption to 80% FC did not impact yield at any development stage, including FS, due to the larger sink of fruit rather than maintaining ideal photosynthetic conditions. ABA and PIP expression increased, which may serve as a signal for the plant to overcome the moderate stress generated by LI.

Organo Mineral Fertilizers Increases Vegetative Growth and Yield and Quality Parameters of Pomegranate cv. Wonderful Fruits

In recent years, to improve sustainable production in horticultural crops, many new types of strategies have been developed, including organo-mineral fertilization to complement chemical fertilizers in order to enhance the nutritional status of plants and sustainability of the agroecosystems. This study was performed on a young pomegranate orchard of the “Wonderful” cultivar during the 2018 and 2019 seasons. The purpose was to evaluate the effects of three foliar applications (at the red ball, fruit setting, and fruit development stages) of four commercial organo-mineral fertilizers (Hendophyt®, Ergostim XL®, Siapton® 10L, and Allibio Rad®) on vegetative growth, yield, and several other physico-chemical parameters of the fruits, throughout each season. The results obtained showed several differences between the two years. The annual trunk growth of trees under all compared treatments showed significantly lower values in 2018 (average 9.7 mm) than in 2019 (average 11.8 mm). At the end of the two-year period, the biostimulant treatments resulted in significantly larger trunk diameters (average 43.6 mm) than the control (39.6 mm). Only in 2018, significantly higher number of fruits per tree, number of arils per fruit, edible part, and juice yield were obtained under biostimulant treatments compared with the control. No differences among treatments were observed for any color parameters or physico-chemical traits in the fruits for either year. In 2019, fruit morpho-pomological properties tended to be lower than in 2018, while in contrast, total phenol content and antioxidant activity were higher. The warmer and windier weather conditions of 2019 probably led to greater plant stress conditions, with a reduction in fruit size and an increase in the bioactive compounds of juice. In conclusion, due to the various positive results, foliar organo-mineral fertilizers could be recommended to improve the performance of pomegranate Wondeful cv. under similar conditions.

Assessment of Thrips Diversity Associated with Two Olive Varieties (Chemlal & Sigoise), in Northeast Algeria

In this study, the diversity of thrips (Insecta: Thysanoptera) on two varieties of olive trees (Chemlal and Sigoise) in northeast Algeria (Province of Batna), was evaluated for 3 years (2019–2021). In addition, the fluctuations in the numbers of phytophagous thrips were estimated according to the varieties phenological stages. A total of 19 species are identified and the olive thrips (Liothrips oleae) have just been reported for the first time in Algeria. Only 5 females of this species were collected in May 2021 on the Sigoise variety at the fruit-setting stage. Haplothrips tritici(17.25%), Frankliniella occidentalis (16.29%) and Thrips tabaci (16.29%) are the most present. It is noticed that the thrips were present on the olive tree only in spring (April to May), when the average monthly temperatures are between 10–26 °C, but linear regression analyses were not confirmed that temperature explain the variation in thrips numbers, which may be due to other climatic factors such as the rainfall, while olive varieties and phenological stages are affecting the population of thrips, their number was higher on the Sigoise variety, especially at flowering stage in the case of H. tritici and F. occidentalis while T. tabaci was most noticeable at the fruit growth stage. The number of this species was relatively low, just until the inflorescence stage, where thrips start to appear in Sigoise before Chemlal.

Foliar Fertilization of Potassium Silicon Improved Postharvest Fruit Quality of Peach and Nectarine [Prunus persica (L.) Batsch] Cultivars

Peach fruit quality is dependent on preharvest treatments and orchard practices. The aim of this study is to evaluate the effects of preharvest potassium silicon fertilization on fruit postharvest quality. Two peach cultivars (“Early Bomba” and “Plagold 17”) were sprayed with three concentrations of potassium silicon (K-Si) at fruit set, stone hardening, and physiological maturity stages. The applied treatments corresponded to control (T0 = 0% K-Si) pulverized with distilled water and two K-Si treatments (T1 = 3% K-Si and T2 = 4.5% K-Si). The blooming and harvesting dates, vegetative growth and agronomical parameters were analyzed over two growing seasons (2021–2022). Peach fruits were stored at 5 °C and 95% RH during two cold storage periods (2 and 4 weeks) followed by 2 days at room temperatures. The fruit weights (FW), color, firmness, soluble solids content (SSC), titratable acidity (TA), pulp stone ratio (P/S) and fruit weight loss (FWL) were evaluated. The anthocyanins, flavonoids, total phenolics, carotenoids and antioxidant capacity (DPPH) were determined. Vitamin B5 and vitamin C were analyzed by HPLC. The ethylene rate and the chilling injury symptoms (CI) were analyzed after two cold storage periods (2 and 4 weeks). Results showed that the applied potassium silicon treatments (3% K-Si and 4.5% K-Si) enhanced the FW, SSC, TA, FWL, fruit composition and CI. Anthocyanins and total phenolics increased after cold storage period under K-Si treatments. The nectarine cultivar (cv) Early Bomba showed low sensibility to chilling injury symptoms as compared to the cv Plagold 17.

Effect of soil water content threshold on kiwifruit quality at different growth stages with drip irrigation in the humid area of Southern China

• Effects of soil water content threshold (SWCT) on kiwifruit quality depended on SWCT timing and degree. • SWCT of 55% field capacity (FC) increased fruit volume and fruit weight at bud burst to leafing stage. • SWCT of 65% FC elevated total soluble solids, soluble sugar and solid-acid ratio at fruit growth stage. • SWCT of 60% FC improved firmness, total soluble solids, soluble sugar, vitamin C and solid-acid ratio at fruit maturation stage. Fruit quality as affected by soil water content threshold levels (SWCT) at different growth stages remains largely elusive. Therefore, a drip irrigation experiment was conducted to investigate the effect of SWCT on kiwifruit quality at bud burst to leafing stage (stage I), flowering to fruit set stage (stage II), fruit growth stage (stage III) and fruit maturation stage (stage IV) during 2018 and 2019 in the humid area of southern China, respectively. The results showed that SWCT at stage I mainly affected fruit weight (Fw). I-55% treatment significantly elevated Fw by 11.6%-8.0% ( P < 0.05). SWCT at stage II had little effect on fruit quality. SWCT at stage III influenced fruit volume (Fv) and chemical quality. Specifically, Fv was increased by 8.0%-2.2% under III-75% treatment, total soluble solids (TSS), soluble sugar (SS) and solids-acid ratio (SOAR) were increased by 9.4%-10.0% ( P < 0.05), 2.4%-5.8% and 7.9%-10.6% ( P < 0.05) under III-65% treatment, respectively. SWCT at stage IV impacted fruit firmness (Fn) and chemical quality. IV-60% treatment increased Fn, TSS, SS, VC and SOAR by 5.6%-10.5%, 12.0%-12.6% ( P < 0.05), 6.6%-9.1% ( P < 0.05), 2.1%-14.0% ( P < 0.05), and 8.1%-8.3% ( P < 0.05), respectively, which was beneficial to the improvement of nutritional value and taste, and also the storage and transportation of kiwifruit. Collectively, SWCT of 55% FC (field capacity) at stage I or 65% FC at stage III or 60% FC at stage IV was an effective measure to improve the kiwifruit quality.

番茄生长过程储存模态信息的植株生物电路模型构建

During the growth and development of tomato plants, its different cells or tissues would store external environmental information and express it in the form of ion transportation. In order to better examine the storage model of tomato plants, the tomato individual tissue and whole plant biological circuit models were closely examined based on the idea of modal theory. According to the parameter inversion theory, in the frequency range of 0.1Hz - 1MHz, the impedance spectrum measurement and dielectric properties of tomato plants in four modal periods of germination stage were carried out. The stages were namely the seedling stage, flowering and fruit setting stage, and fruiting stage respectively. Impedance spectrum fitting was performed with the ZSimpWin software. Then, the biological circuit model of each tissue of tomato plant was obtained. Next, the parameter inversion was used to calculate the value of each element of the biological circuit model. Lastly, the biological circuit model of the tomato plant body in each period was obtained. Through the charging and discharging test of the model of the tomato plant body at each stage, the corresponding parameter value relationship was obtained according to the capacitance characteristics. This would be compared with the component values obtained from the parameter inversion in the model. Results showed that the errors were all less than 4.8%, which verified the rationality of the model. This system acted as a theoretical guidance for the research on the growth and development of tomato and other plants.

Chemical Composition and Antioxidant and Antibacterial Potencies of the Artemisia ordosica Aerial Parts Essential Oil during the Vegetative Period.

As one of the vital shrubs growing in crusted areas in China, Artemisia ordosica (belonging to the Asteraceae family) is abundant in essential oil, and its aerial part's essential oil has been reported to have some biological activities during the flowering and fruit set stage, and has been used in folk medicine. However, little is known about the biological activities of its aerial part's essential oil during the vegetative period. Thus, the purpose of this work was to determine the chemical composition and evaluate the antioxidant and antibacterial potencies of the essential oil extracted from A. ordosica aerial parts during the vegetative stage. Gas chromatography coupled with mass spectrometry (GC-MS) revealed that spathulenol (9.93%) and α-curcumene (9.24%), both sesquiterpenes, were the most abundant of the 74 chemical constituents detected in the essential oil of A. ordosica. The antioxidant activity of the essential oil was found to be relatively moderate against 2,2-diphenylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical (OH●) radicals. The essential oil exhibited strong antibacterial activity against Staphylococcus aureus, Salmonella abony and Escherichia coli, with minimum inhibitory concentrations (MICs) of 2.5, 5, and 10 μL/mL, respectively. The results indicate that the essential oil of A. ordosica possesses notable antibacterial properties as well as antioxidant capability and can thus be employed as a natural ingredient which can be used as a substitute for antibiotics in the animal feed industry. However, in vivo toxicological studies are still required to determine the safety level and beneficial outcomes of the A. ordosica essential oil for future utilization.