Subtropical Conditions Research Articles

Comparison of the Morphological Characteristics, Yield, and Quality Traits of Fruits of Two Papaya Cultivars Grown Under Protected Cultivation

This study aimed to investigate the morphological characteristics and performance of Formosa and Sunrise Solo papaya cultivars under protected cultivation in subtropical climate conditions as well as the relationships between the yield and factors affecting the yield. The Formosa cultivars had higher values in terms of plant height (519.4 cm), stem diameter (238.4 mm), first flowering height (138.2 cm), and duration from flowering to harvest (141 days) compared to the Sunrise Solo cultivars. The yield per plant was higher in the Formosa cultivars (52.5 kg/plant/year) than in the Sunrise Solo cultivars (27.4 kg/plant/year). The values of fruit peel color parameters were highest in the spring, the fruit flesh firmness was highest in the autumn, and the soluble solid content was higher in fruits harvested in the summer. Medium to high positive phenotypic correlations were found between the first flowering height and fruit set, fruit weight, yield, fruit width, fruit length, and fruit flesh firmness (0.371–0.595) and between the fruit set (number/plant) and fruit weight, yield, fruit width, fruit length, and fruit flesh firmness (0.388–0.819) (p ≤ 0.01). The papaya can be commercially cultivated under protected cultivation in extreme subtropical conditions, and the Formosa cultivars generally performed better than the Sunrise Solo cultivars across many parameters.

Influence of Natural Dyes on the Qualitative and Quantitative Parameters of Bivoltine Silkworm Breeds under Sub-Tropical Conditions of Poonch District, Jammu and Kashmir

The study on Influence of Natural Dyes on the qualitative and quantitative parameters of Bivoltine Silkworm Breeds under Sub-tropical Conditions of Poonch District, UT Jammu and Kashmir,” was conducted during the spring of 2022 at the PG, Department of Sericulture, Poonch Campus, University of Jammu. The study examined the effects of feeding bivoltine silkworm breeds CSR16 and CSR27 with two concentrations (50% and 100%) of natural dyes: madder (Rubia cardifolia) and indigo blue (Indigofera tinctoria). A comprehensive evaluation of both qualitative and quantitative parameters was undertaken, including fecundity, hatching %, larval duration, weight of 10 mature larvae, survival rate, mortality %, pupation % and cocoon quality parameters. The results indicated significant enhancements in fecundity, hatching % and cocoon yield for silkworms treated with both dyes at 100% concentration (T2). Specifically, CSR16 and CSR27 exhibited the highest values for larval weight, cocoon weight, pupation rate and shell ratio % in T2 treatments. The findings suggest that feeding silkworms natural dyes, particularly at higher concentrations, significantly improved the economic parameters of both breeds. While the cocoons produced were intrinsically coloured without compromising commercial parameters, the colour intensity was lighter than anticipated. This implies that introducing dyed mulberry leaves during the 1st instar stage may yield more favourable results. Overall, the study demonstrates that madder and indigo dyes are suitable for producing coloured silk, offering potential for large-scale applications in sustainable silk production.

Optimization of trellis design and height for double-season hop (Humulus lupulus L.) production in a subtropical climate: Growth, morphology, yield, and cone quality during establishment years

Photoperiod manipulation using supplemental lighting enables double-season production of hops (Humulus lupulus L.) under subtropical climatic conditions. In Florida, United States, the spring growing season (Spring) is from February to June, and the fall growing season (Fall) is from June to November. To develop the optimum trellis for this unique hop production system, we examined the effects of two trellis designs (straight trellis and V-trellis) and three trellis heights (3.7, 4.6, and 5.5 m) on growth, morphology, yield, and cone quality of 'Cascade' hops grown in west central Florida. The straight trellis had two twines per hill installed on a top middle cable, whereas the V-trellis had four twines per hill installed on two top parallel cables. We trained 16 bines per hill for both trellises. Data were collected during establishment years: Year 1 and Year 2. Yield showed significant season × trellis height interaction effects. Surprisingly, yield was highest in Year 1 Spring and decreased by 45–74 % in the subsequent seasons. Increasing trellis height from 3.7 to 5.5 m increased yield by 78–215 %. On average, the V-trellis produced 24 % higher yield than the straight trellis. The 5.5-m V-trellis produced the highest annual yield of 1807 kg ha–1 in Year 1. Yield had a significant positive correlation with stem dry weight in Year 1 Spring and Year 2 Spring, but it had no significant correlation with bine number per hill, stem diameter, and internode length in any season. Cone quality showed significant seasonal variations. Total α acid concentration decreased from Spring to Fall in both years and recorded the highest value in Year 2 Spring. Similarly, total essential oil content was highest in Year 2 Spring. Except in Year 2 Fall, total α acid concentration (5.35–8.25 %) was within or above the normal range for ‘Cascade’. Compared to these seasonal variations, trellis design and height effects on cone quality were relatively small. These results suggest that, during establishment years, adopting a V-trellis design and increasing trellis height can maximize yield in subtropical hop production without compromising overall cone quality. Ongoing research will validate these findings in mature hop plants.

Optimizing wheat supplementary irrigation: Integrating soil stress and crop water stress index for smart scheduling

A two-year field experiment was conducted to integrate soil moisture stress with the Crop Water Stress Index (CWSI) for optimizing irrigation in winter wheat (Triticum aestivum L.) under varying irrigation regimes. The study took place at the Water Technology Centre (WTC-02) of ICAR-IARI, New Delhi, where the climate shows a blend of monsoon-influenced humid subtropical and semi-arid conditions. Using a randomized block design (RBD), five irrigation treatments were applied: full irrigation and deficit irrigation (DI) at 15 %, 30 %, 45 %, and 60 % levels. Canopy and ambient air temperature data, along with vapor pressure deficit (VPD), were recorded using a developed integrated sensing device to empirically determine the lower baseline equations and upper threshold for CWSI computation at pre-heading and post-heading stages. The slope (m), intercept (c) of the lower baseline equation, and upper threshold (UL) for pre-heading and post-heading were found: m: −1.94, c: −1.33, UL: 1.92°C and m: −1.30, c: −2.37, UL: 2.0°C, respectively. Results showed that increasing water deficit levels led to significant reductions in grain yield, biomass production, and harvest index. A strong negative correlation (R² = 0.95 and 0.93) between mean seasonal CWSI and yield attributes highlighted the utility of CWSI in yield prediction under varying irrigation regimes. It is recommended to schedule irrigation based on the CWSI approach when CWSI ≥0.35 for optimum wheat yields. Integrating CWSI with soil moisture stress provides valuable real-time insights into crop water status, enabling more precise and smart irrigation scheduling.

Space-time analysis, severity of the wilt disease in escabeche pepper (Capsicum baccatum var. Pendulum) and identification of the causal agent (Phytophthora capsici L.) under subtropical climate conditions in Peru

Phytophthora capsici is an aggressive pathogen in escabeche pepper on the Peruvian coast. Root rot has a strong correlation with humidity and environment. Disease behavior was evaluated epidemiologically using spatiotemporal variables. Severity was evaluated according to the advance of the secondary symptom according to grades 1 to 5. Then, coordinates of each plant were established by photogrammetric survey of a field with 1705 escabeche pepper plants. For temporal analysis, severity was adjusted to an exponential model (R2 = 0.909) and incidence to a Gompertz model (R2 = 0.921) that detected an initial delay of the disease due to temperature. For the spatial analysis, the Global Moran Index (Ii) showed a high spatial dependence of the disease reaching a peak of 0.4 and 0.7 for severity and incidence, respectively. Also, heat maps related to the Local Ii were generated from which an initial source of infestation was determined where the furrow irrigation started in random infestations. Then, the infestation spots were settled in areas of surface water accumulation. Also, rhizosphere samples were collected per plant by degree of severity on V8 or CMA whit PARB and PDA-A selective medium. As a result, significant differences were obtained between grade 1, grade 2, 3, 4 and grade 5. In addition, the effect on yield was significant for plants with grade 4 and 5 with respect to fruit weight (22.3 and 18.5g/fruit) and weight per plant (509.5 and 371.8g/plant), respectively.

Foraging behaviour and pollinator dynamics in lucerne crop of the Bundelkhand region: Implications for crop management in the subtropics

Abstract Pollination stands out as the paramount ecosystem service facilitated by insect pollinators, providing benefits to over three quarters of the world’s major crops. The conservation and effective management of honeybees constitute integral components for ensuring the sustainable productivity of cross-pollinated crops. The present study aimed to document the potential pollinators of lucerne in the Bundelkhand region in India, which is known for its subtropical climatic conditions. Further, the foraging behaviour, including foraging rate and speed, was meticulously documented. A total of 13 insect species from seven families across three insect orders were observed visiting lucerne flowers. Hymenopterans comprised the majority of the floral visitors (73.48%), followed by Lepidoptera (26.51%) during the study period. Among them, Apis dorsata (Hymenoptera: Apidae) emerged as the most predominant floral visitor, exhibiting peak activity at 12:00 h with a density of 7.85 bees/m2/10 min. Surprisingly, among the major floral visitors, A. florea has the highest mean foraging rate (number of flowers visited/minute/forager), i.e., 11.56, 11.59 and 10.79 bees/flowers/minute during the initial flowering stage, peak flowering stage and late flowering stage, respectively. However, the foraging speed (time spent by the forager on each flower) was longest in A. dorsata, i.e., 5.05, 3.78 and 5.41 s/flower during initial, peak and late flowering stages, respectively. The findings emphasize the importance of enhancing honeybee activity to boost lucerne seed yield. Further, the outcomes of the study can be leveraged to optimize honeybee colony management, scheduling field operations such as pesticide application and weeding during periods of minimal honeybee activity.

Paleoenvironmental conditions across the Coniacian-Santonian in the Kometan Formation, northeastern Iraq: Insights from planktonic foraminifera distribution, mineralogy and geochemistry

The paleoenvironmental conditions during the Coniacian-Santonian interval within the Kometan Formation in northeastern Iraq have been analyzed through the distribution of depth-related planktonic foraminifera in the carbonate rocks (limestone and marly limestone) of the Kometan Formation using standard washing method for soft samples and thin section method for hard samples supported by mineralogical investigations, geochemical analysis and stable isotopic δ13C and δ18O data. The findings indicate that saline marine waters and a hot, dry to semi-arid climate with low to medium oxygen conditions were conducive to deposition, which was characterized by high organic productivity due to marine transgression. The study revealed that the distribution of shallow water forms (SWF) of globular-shaped foraminifera, compared to deep water forms (DWF) of keeled-shaped genera, along with δ13C data from the late Turonian-early Campanian succession, indicated a relatively low sea level throughout the Late Turonian period. The water level began to rise in the early Coniacian, continuing gradually until the late Coniacian, when a noticeable increase in sea level was observed. This elevated sea level persisted through the early and late Santonian periods, before starting to drop. A slight marine transgression was noted at the beginning of the early Campanian period, followed by a significant drop in sea level. During the late Turonian, a subtropical climate prevailed. Temperature increased during the early to middle Coniacian, decreased slightly at the beginning of the late Coniacian, and then rose again at the end of the late Coniacian, indicating a shift from tropical to subtropical climatic conditions. Similar hot climatic conditions persisted in a tropical-subtropical climate during the early to late Santonian and early Campanian, with a relative temperature drop near the end of the early Campanian. No evidence of an oceanic anoxic event (OAE3) was found in the Kometan Formation during the late Coniacian–early Santonian period. The hypothesized event, based on biostratigraphy, facies analysis, stable isotopes, geochemical evidence, and field study, was limited to demonstrating an increase in the ratio of keeled chamber planktonic foraminifera compared to globular chamber ones. This ratio increase of the keeled chamber types is believed to result from a deepening sedimentary environment due to rising sea levels, creating organic matter-rich beds with high productivity and relatively low oxygen conditions during the Coniacian-Santonian boundary.

Temporal effect of flaxseed oil in boar’s diet on semen quality, antioxidant status and in-vivo fertility under hot humid sub-tropical condition

The present study investigates the temporal effects of flaxseed supplementation on boar semen quality, antioxidant status, and in-vivo fertility under high-temperature humidity index (THI) conditions in a sub-tropical climate. Twelve Hampshire crossbreed boars were randomly assigned to control and treatment groups, with the treatment group receiving flaxseed oil supplementation. Semen samples were collected and analyzed for semen quality parameters, sperm kinematics, and antioxidant status. Fertility outcomes were assessed through in-vivo mating trials. Flaxseed supplementation resulted in time dependent significant improvements in semen volume, sperm concentration, total and progressive sperm motility, sperm quality parameters, and antioxidant status. Fertility outcomes, including farrowing rates and litter sizes, were also enhanced in the flaxseed-supplemented group. These findings highlight the potential of flaxseed supplementation to improve boar fertility under high ambient stress conditions, with implications for optimizing reproductive performance in swine production systems.

Optimum Utilization of Different Nitrogen Fertilizer Sources for Improving Soil Properties and Agro-Physiological Indices of Maize Crop under Humid Subtropical Conditions of Pakistan

Optimum Utilization of Different Nitrogen Fertilizer Sources for Improving Soil Properties and Agro-Physiological Indices of Maize Crop under Humid Subtropical Conditions of Pakistan

Assessing ecological responses of exposure to the pyrethroid insecticide lambda-cyhalothrin in sub-tropical freshwater ecosystems

Pyrethroid insecticides are widely detected in aquatic ecosystems due to their extensive use in agriculture and horticulture, which could pose a potential risk to aquatic non-target organisms. While previous ecotoxicological studies have been conducted mainly with standard tests and local species under temperate conditions, scarce information is available on the effects of pyrethroid insecticides on communities and ecosystems under (sub-)tropical conditions. A single application of lambda-cyhalothrin at concentrations of 0, 9, 30, and 100 ng/L was evaluated in outdoor mesocosms under sub-tropical conditions. Lambda-cyhalothrin was found to dissipate rapidly in the water column, with only 11 % and 7 % of the remaining dose measured at 1 and 3 days after application, respectively. Lambda-cyhalothrin concentrations disappeared considerably faster from the water compartment compared to temperate conditions. Consistent decreases in abundance were observed for Lecane lunaris at the medium and higher treatments (NOEC = 9 ng/L) and at the highest treatment (NOEC = 30 ng/L) for Keratella tropica. On the contrary, two taxa belonging to Cladocera (i.e., Ceriodaphnia sp. and Diaphanosoma sp.) showed the most prominent increase in abundance related to the lambda-cyhalothrin treatments. At the community level, a consistent no observed effect concentrations (NOECs) of 9 ng/L could be calculated for the zooplankton community. A marginal significant overall treatment related effect was observed for the macroinvertebrate community. The results of species sensitivity distribution (SSD) analysis based on results of acute toxicity experiments conducted alongside the mesocosm experiment and obtained from the literature indicated that macroinvertebrates from temperate regions may be generally more sensitive than their counterparts in (sub-)tropical regions. Overall, these findings suggest that environmentally relevant concentrations of the pyrethroid insecticide lambda-cyhalothrin may lead to different ecological outcomes in freshwater ecosystems in the (sub-)tropics relative to temperate regions.

Response of actinidia deliciosa plants to abiotic stress in the Russian subtropical zone

The article presents a general description of the culture of Actinidia deliciosa, grown in the humid subtropics of Russia. The work was carried out since 2017 at the site of the Adler experimental station of the branch of the Federal Research Center of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources and in the laboratory of plant physiology and biochemistry of the Subtropical Scientific Center of the Russian Academy of Sciences, Sochi. Physiological and biochemical indicators were determined that reflect the resistance of actinidia plants planted in 1988 to environmental stress factors to identify the most adapted varieties to the conditions of the humid subtropics of the Krasnodar Territory. The soil is alluvial meadow with low humus. The varieties studied were late ripening Hayward; Ellison, Abbott and Bruno – early; Monty – medium; Tomuri (pollinator of kiwi female varieties). The indicator organ is physiologically mature actinidia leaves, which were selected from May to September against the backdrop of a natural increase in air temperature. Water deficit was in 2022–2023 is 29.62–36.46%, the minimum is for the Ellison and Monty varieties (29.62–30.21), the maximum is Abbott (36.46%). The dry matter content is 25.47–35.53%, the water content of leaf blades is 46.09-62.66%. The Monti, Hayward and Tomuri varieties are the most resistant to the weather and climatic conditions of the Russian subtropical zone.

NUTRITIVE VALUATION OF WINTER FORAGE CEREALS HAY UNDER VARIABILITY OF AGRO-CLIMATIC CONDITIONS AND NITROGEN REGIMES AT BOOTING STAGE

The fundamental relation between forage growers of rain fed areas of Azad Jammu and Kashmir and Pakistan is intense fodder shortage in winter season. The study focused to investigate the inconsistency of winter forage cereals WFCs (barley, oat, rye and triticale) to compute precise dose of nitrogen (0, 75, 150 and 225 kg.ha-1) for the assessment of nutritive evaluation of WFCs, hay at booting stage BS under temperate conditions of (Rawalakot) and subtropical conditions of (Rawalpindi). The two years (2016-2017, 2017-2018) field experiments were, examined at research farm (Chottagalla) of University of Poonch Rawalakot and research farm of (Koont) Arid Agriculture University Rawalpindi. In both locations at BS, the hay samples were properly harvested, tagged and arranged. During corresponding years, Rye (12.9%, 13.1%) at Rawalakot while oat (11.2%, 11.5%) at Rawalpindi produced more crude protein contents in response with N @ 225 kg ha-1. The extreme amount of crude fiber contents, acid detergent fiber and neutral detergent fiber contents were documented, for rye at Rawalakot, whereas for oat at Rawalpindi conditions in response to N @ o kg ha-1. Throughout both years, the highest ash contents were recorded, for rye (13.27%, 13.48%) at Rawalakot, whereas triticale (11.42% 12.11%) and oat (11.2%, 11.89) were statistically same under Rawalpindi conditions with application of N @ 225 kg ha-1. It is concluded; from experimental results, there is dire need for nitrogen application to optimize the yield and nutritional value of WFCs under both climatic conditions.

Dynamics of productivity in pigeonpea [Cajanus cajan (L.) Millsp.] in subtropical Australia

AbstractPigeonpea productivity can be enhanced by optimally matching the physiology of genotypes to environmental conditions. Information on crop responses to the environment has been lacking for the short‐duration pigeonpea genotypes, which are being trialed to develop the Australian pigeonpea industry. The objective of this study was to examine the dynamics of productivity in relation to radiation use efficiency (RUE) and its influence on yield partitioning. Seven field trials, employing three pigeonpea [Cajanus cajan (L.). Millsp.] genotypes, were established at the Gatton Campus, the University of Queensland, Australia, in 2017/2018 and 2018/2019 summer seasons. The study reveals that leaf area development, influenced by growing environment, genotypes, and their interactions, were the key factors for the differences in leaf area duration and RUE. Pigeonpea planted in December had higher seasonal (1.11 g MJ−1) as well as reproductive (0.71 g MJ−1) RUE, resulting in significant differences in total dry matter (TDM) and grain yield (GY). GY was positively associated with seasonal RUE (R2 = 0.62), and the relationship was stronger (R2 = 0.83) for the reproductive phase (RUE(R)). The positive association between GY and RUE(R) suggested that maintaining optimum leaf area during the grain filling period is crucial to achieve higher productivity. Variations in GY were related to amount and rate of TDM accumulation before flowering (R2 = 0.51 and R2 = 0.53, respectively). Hence, achieving greater TDM before flowering was determinant for achieving higher productivity. The present study provided updated information on dynamics of productivity that will enable more comprehensive modelling of pigeonpea adaptation under subtropical conditions.

Effect of Exogenous Application of Humic Acid, GA3 and Vermiwash on Growth, Yield and Quality of Cabbage (Brassica oleracea var. capitata L.) under Valley Condition of Srinagar Garhwal

The effect of exogenous application of humic acid, GA3 and vermiwash on the growth, yield and quality of cabbage was studied in a field experiment. The experiment was conducted in a randomized block design at the Horticultural Research Centre, Chauras Campus, H.N.B. Garhwal University, Srinagar, Uttarakhand, with three replications and ten treatments. All of the growth, yield and quality contributing characteristics of cabbage were found to be significant. The growth parameters at 30, 45 DAT and at harvest were found to be maximum under T9 (GA3 @ 150 ppm). Yield parameters were found to be highest in T9 (GA3 @ 150 ppm) total plant weight (2188.67 g), average weight of head (1454.33 g), yield per hectare (321.43 q) whereas dry weight of head (10.00 g) in T6 (Vermiwash @ 100%), head diameter (18.98 cm) and core diameter (4.53 cm) in T8 (GA3 @ 100 ppm) and core length (8.62 cm) in T1 (Humic acid @ 100 ppm). Quality parameters were found to be highest under T6 (Vermiwash @ 100%) for head compactness (35.39%), whereas total soluble solids (5.20 0Brix) in T3 (Humic acid @ 200 ppm) and ascorbic acid (56.07 mg) in T1 (Humic acid @ 100 ppm). Economic parameters were found to be highest under T6 (Vermiwash @ 100%) for cost of cultivation (1,92,510 ₹/ha), gross return (10,66,030 ₹/ha) and net return (8,73,520 ₹/ha). Hence, it may be suggested that concentration of 150 ppm GA3 could use for enhancing the production of cabbage under subtropical condition of Srinagar Garhwal

Nitrogen Dynamics from Conventional Organic Manures as Influenced by Different Temperature Regimes in Subtropical Conditions

Determining nutrient-release patterns of organic manures can give an estimate of the potential amount of nutrients that a given material can contribute to crops along with chemical fertiliser. Nutrients released from organic manure depend on several factors, and temperature is one of them. To evaluate how different types of conventional organic manures release nitrogen (N) under varying temperature conditions, an incubation study was conducted at the Bangladesh Agricultural Research Institute. Six organic manures—poultry manure (PM), vermicompost (VC), bio-slurry (BS), cowdung (CD), water-hyacinth compost (WHC), and rice straw compost (RSC)—were evaluated at three temperature regimes (15, 25, and 35 °C) to study the dynamics of N incubated for 330 days. The N release was significantly influenced by the interaction of organic manures and temperature regimes. Poultry manure-treated soil incubated at 35 °C had the highest mineralisation of all parameters than other manures. The mineralisation of N followed the order: PM > VC > BS > CD > WHC > RSC > control and 35 °C > 25 °C > 15 °C. Across different temperatures, the mineralisation rate of PM was 15–55% higher than that of other manures. At 35 °C, the mineralisation rate was 10% and 20% higher compared to 25 °C and 15 °C, respectively. The first-order kinetic models predicted the organic N release from manures satisfactorily. The findings of the present study enrich the understanding of N-release patterns under different temperature regimes that prevail in different crop growing seasons in Indo-Gangetic Plains, providing valuable data for researchers and policymakers interested in sustainable integrated nutrient management practices.

Application of (U-Th)/He hematite geochronology to the Çaldağ lateritic Ni-Co deposit, Western Anatolia: Implications for multi-stage weathering events during interglacial periods/segments

Lateritic Ni-Co deposits are supergene deposits that develop due to intense weathering of the underlying ultramafic parent rocks and/or their serpentinized equivalents under tropical to sub-tropical climatic conditions. These deposits provide not only important sources of valuable metals such as iron, aluminium, nickel, and cobalt, but they also provide a proxy for paleoclimatic conditions. In this regard, geochronological studies on these deposits are critical to determine the timing of the paleoclimatic conditions, which is important for a better understanding of the paleoclimate at regional scale and for identification of favourable weathering periods that can be targeted in the exploration of undiscovered lateritic deposits in a region. In this contribution, we report hematite (U-Th)/He geochronology results from a well-preserved Çaldağ lateritic Ni-Co deposit in Western Türkiye. We sampled the different parts of the lateritic profile from the different laterite zones at the Çaldağ deposit and carried out analyses of polished thin section to determine and identify the phases of hematite formation and primary hematite formed during primary lateritization. Then, we applied scanning electron microscopy (SEM) analysis and TESCAN Integrated Mineral Analyser (TIMA) mineral mapping to identify the suitable areas on primary hematites for subsequent (U-Th)/He dating.Primary hematites are detected at the base of the lateritic profiles (transition between the limonite zone and altered serpentinite) that are only in-situ parts of the laterites exposed in two different pits in the deposit. The obtained (U-Th)/He dates of ca. 502, 206, 178, and 63 ka correspond to the interglacial periods. The three youngest (U-Th)/He dates (206, 178, and 63 ka) from the weathering front of the hematite pit become younger towards the deeper parts of the profile in the direction of weathering. The ages indicate the weathering processes should have lasted until the Quaternary with some interruptions during interglacial periods/segments, despite the fact that the main intensive lateralization period is thought to be during the Middle Eocene.This study presents the first hematite (U-Th)/He dating of lateritic Ni-Co deposits and demonstrates the reliable use of this method after a careful selection of hematite samples. Our results suggest that, in contrast to the short-living lateritization model for lateritic Ni-Co deposits, they may have a multi-stage weathering history throughout their long-lasting development. In addition, the study showed that it has huge potential for the dating of lateritization and weathering processes that are related to paleoclimatic events. Finally, knowledge of the favourable paleoclimatic periods of chemical weathering in a region may help in determining the potential areas for ultramafic exposures for discovering new lateritic deposits.

Comparative analysis of breeding patterns and reproductive efficiency of mares in subtropical conditions of Pakistan.

The present study aimed to evaluate and compare the overall and breed-specific seasonal breeding patterns, fertility rates, cyclicity, and follicular dynamics of Arab, Thoroughbred, and Percheron mares under the subtropical conditions of Pakistan. A retrospective analysis of climatic data and breeding records of eleven breeding studs spanning four years (2020-2023) was made to find out the overall seasonality in the breeding pattern of mares. Fifty mares of each breed (n=150 in total) were scanned by ultrasonography for a calendar year to find the cyclicity pattern and follicular dynamics (follicular growth rate, size of ovulatory follicle, and days from estrus till ovulation). The statistical analysis of breeding records demonstrated a clear pattern of seasonal breeding (p<0.05). The highest monthly foalings were noted in March (247±45.37), and overall breeding activities peaked in Spring season (p<0.05). Breed-specific results of Arab, Thoroughbred, and Percheron mares revealed that Arab mares maintained stable breeding activity throughout the year, with the highest activity in spring and peak conception rate in winter (56.25%±32.78; p>0.05). Thoroughbred mares experienced significant seasonal declines from spring to winter with a peak conception rate in winter (63.89%±27.37, p>0.05). Percherons showed the most pronounced seasonal effects, especially with a high fall conception rate (73.04%±19.61) and a sharp decrease in winter breeding metrics (p<0.05). Furthermore, Thoroughbred and Percheron mares displayed the most pronounced seasonal effects on the percentage of cyclic mares 77.3% and 56% in winters (p<0.05). Moreover, the follicular dynamics of the three breeds also exhibited significant differences (p<0.05). The current study concludes that seasonal and breed-specific variability exists among the reproductive parameters of Arab, Thoroughbred, and Percheron mares in subtropics, necessitating breed-specific reproductive management measures to maximize mare breeding efficiency.

Effect of foliar application of plant growth regulators on incidence of insect-pests and diseases in autumn planted seed potato (Solanum tuberosum)

A field experiment was conducted during 2019–20 and 2020–21 at Punjab Agricultural University, Ludhiana, Punjab to study the effect of foliar application of plant growth regulators on insect-pest and disease incidence in potato (Solanum tuberosum L.) under subtropical conditions. A total of 11 treatments including control were tested in a randomized complete block design (RCBD) with three replications on the potato cv. Kufri Pukhraj. The results indicated that plant growth regulators, like GA3, IBA, NAA, ethrel, jeevamrit and waste decomposer were not producing any significant effect on the incidence of aphid, jassid and whitefly population in comparison to untreated control. However, diseases such as scab and scurf did not reveal any significant differences among the plant growth regulator’s treatments except in late blight. Foliar application of gibberellic acid (200 ppm) at 45 and 60 days after sowing (DAS) significantly reduced the late blight incidence and severity in seed potato cv. Kufri Pukhraj.

IGF-I and GH Genes polymorphism and their association with milk yields, composition and reproductive performance in Holstein–Friesian dairy cattle

BackgroundThe insulin-like growth factor (IGF-I) and growth hormone (GH) genes have been identified as major regulators of milk yield and composition, and reproductive performance in cattle. Genetic variations/polymorphism in these genes have been found to influence milk production, yield and quality. This investigation aimed to explore the association between IGF-I and GH polymorphisms and milk yield and composition, and reproductive performance in a herd consisting of 1000 Holstein–Friesian (HF) dairy cattle from El-Alamia farm. The experimental animals were 76 ± 7.25 months in age, with an average live weight of 750 ± 50.49 kg, and raised under the same conditions of feeding and weather. The studied animals were divided into three categories; high producers (n = 280), medium producers (n = 318) and low producers (n = 402).ResultsThe digestion of 249 bp for IGF-I-SnaBI using the Restriction-fragment-length-polymorphism (RFLP) technique yielded two alleles; T (0.59) and C (0.41) and three genotypes; TT (0.52), TC (0.39) and CC (0.09) and this agrees with the results of DNA/gene sequencing technique. The sequencing analysis of the IGF-I gene revealed polymorphism in position 472 (C > T). Nucleotide sequencing of the amplified fragment of the IGF-I gene of different genotypes was done and submitted to the NCBI GenBank with Accession no. MH156812.1 and MH156811.1. While the digestion of 432 bp for GH-AluI using the RFLP technique yielded two alleles; A (0.81) and G (0.19) and two genotypes; AA (0.77) and AG (0.23) and this agrees with the results of DNA/gene sequencing technique. The sequencing analysis of the GH gene revealed polymorphism in the position 1758 C > G and in turn led to changes in amino acid sequence as Alanine for (A) compared to Glycine for (G). Nucleotide sequencing of the amplified fragment of the GH gene was done and submitted to the NCBI GenBank with Accession no. MH156810.1. The results of this study demonstrate the effects of variants of the GH-IGF-I somatotrophic axis on milk production and composition traits in commercial HF cattle. The greatest values of milk yield and reproductive performance were observed on IGF-I-SnaBI-TC and GH-AluI-AG genotypes. While the greatest % fat and % protein values were observed on IGF-I-SnaBI-CC and GH-AluI-AA genotyped individuals.ConclusionThe genetic variation of the studied genes can be utilized in selecting animals with superior milk yield, composition and reproductive performance in Holstein–Friesian Dairy Cattle under subtropical conditions.

Optimization of Ruscus hypophyllum L. Growth Using Manure and Nitrogen Applications in Subtropical Conditions of Punjab

Aims: This study aimed to evaluate the impact of farmyard manure (FYM) and nitrogen (N) on the growth and development of Ruscus hypophyllum L., a valuable cut foliage crop. Study Design: The research was conducted as a two-year field experiment using a randomized complete block design (R.C.B.D.). Place and Duration of Study: The experiment was conducted at the Department of Floriculture &amp; Landscaping, Punjab Agricultural University, Ludhiana, Punjab, during 2020-2021. Methodology: The study utilized four treatments: control, 50 g N + 10 kg FYM, 100 g N + 20 kg FYM, and 150 g N + 30 kg FYM. Key growth parameters measured included plant height, spread, stem diameter, leaf dimensions, and number of harvestable stems. Data were collected and analyzed using standard agronomic methods to determine the effectiveness of each treatment. Results: The 100 g N + 20 kg FYM treatment consistently produced optimal results. Plants under this treatment reached a maximum height of 73.34 cm and had a stem diameter of 1.55 cm. Leaf breadth and length were significantly improved, with values reaching 4.03 cm and 8.05 cm, respectively. The number of harvestable stems increased from 16.66 in the control to 20.5. Higher nutrient levels (150 g N + 30 kg FYM) often reduced performance, indicating potential over-fertilization effects. Conclusion: The findings underscore the importance of balanced nutrient management in R. hypophyllum cultivation. The 100 g N + 20 kg FYM treatment is recommended for optimal growth and yield. These results provide evidence-based recommendations for commercial production, highlighting the need to avoid over-fertilization to prevent reduced plant performance.