Nursery Conditions Research Articles

Propagation technique of <I>Litsea glutinosa</I> (Maida lakri)

Seed germination ofLitsea glutinosa was completed within six weeks with 30.04 p er cent germination in nursery conditions. However, seeds treated with gibbereiiins (500 ppm) gave 41.48 p er cent germination under controlled conditions. Two years old plants were fit for planting out in the field. Air - layering trials were carried out during March to May and developed the callus but rooting was not initiated. Shoot cuttings prepared fromjuveniie plants gave 43.00 percent rooting. Macro - proliferation technique was developed formass multiplication of this endangered species which is found cost - effective, eco - friendly and innovative.

Nursery and field growths of Enterolobium contortisiliquum seedlings produced in different containers and fertilizer doses

Studies on the early development of forest species usually only analyze their nursery growth, not taking the post planting into account. Therefore, this study aimed to evaluate the survival and growth under nursery and field conditions of Enterolobium contortisiliquum seedlings produced with different container volumes and controlled-release fertilizer (CRF) doses. The treatments were composed of two containers volumes (110 and 180 cm3) with five CRF doses (0; 3; 5; 7; and 9 g L-1). At the nursery, at 150 days after sowing, the following attributes were evaluated: height (H); stem diameter (SD); shoot (SDM), root (RDM) and total dry matter (TDM); and Dickson quality index (DQI). At 360 days after the field planting, the survival, H and SD were measured. It was found interaction between factors for SD and significant effects of container volume for SDM, RDM, TDM and DQI. The maximum technical efficiency dose (MTED) of CRF in the nursery ranged from 6.50 to 9.74 g L-1. This allowed recommending the CRF dose for the fast seedling outplanting. The negative effects from base fertilization absence were identified on the seedlings field survival, yet there was no influence of the tested treatments on their growth 360 days after planting. For producing Enterolobium contortisiliquum seedlings, it is recommended using 110 cm3 containers with a CRF dose of 3 g L-1, which provides suitable performance on the outplanting and after it. However, doses above 7 g L-1 can reduce the seedlings nursery time in about six months after sowing.

Economics of producing quality seedlings of important agroforestry species with different growing media under shade-net conditions in semi-arid region of Rajasthan

A field experiment was conducted during June, 2019 to March, 2020 at the Instructional farm Fruit Science at the College of Horticulture and Forestry, Jhalawar, Agriculture University Kota (Rajasthan). The experiment was comprised of eighteen treatments of four growing medium viz.; soil, sand, FYM and Vermicompost in different ratio. The study aimed to find out best growing medium for following three species viz. Ardu (Ailanthus excelsa), Bael (Aegle marmelos) and Neem (Azadirachta indica). Seedlings were raised in the polybags of size 6” x 10” under green shed net (50% light intensity) nursery conditions. Highest Benefit cost ratio of 2.23, 2.97 and 2.23 was observed in T0 with lowest cost of cultivation as used only soil as growing medium for Ardu, Bael and Neem respectively whereas revenue remained constant for Bael Rs.20 per seedling and for Ardu and Neem Rs. 15 only in all the treatments. The results obtained from this study can be used to produce quality planting material of Ardu, Bael and Neem in shortest possible time and lowest quality input.

Field establishment of Abies stocktypes in Christmas tree plantations

ABSTRACT Identification of stocktype attributes that speed up field establishment has potential to reduce rotation time of Christmas tree productions. Such morphological and physiological attributes can be targeted in the nursery production. This study tested the effects of container type and nursery seedling density on stocktype attributes at planting and the effects of these on field performance over two years in Abies lasiocarpa and A. nordmanniana Christmas tree stock. Nursery conditions had a considerable impact on seedling attributes at planting. Although sets of these correlated stocktype attributes contributed to forecast field performance, the predictive power was low. No simple relationships were found between plant biomass, stem diameter or height at planting and biomass at final harvest in either of the two species under the range of stocktype variation and field conditions tested. Contrary, stem diameter and stem height at planting explained some of the responses in stem diameter and height after two years in the field. Thus, any target seedling approach would have to be based on a combined set of stocktype attributes exploring more productive stocktypes. The differences observed between stocktypes were largely due to size differences and ontogenetic drift, and stocktypes converged towards a similar field phenotype over time.

First Report of Erysiphe adunca Causing Foliar Powdery Mildew on Poplar in China

Hybrid poplars are important economic plants and sources of biofuel all over the world. Poplars are subjected to a wide range of diseases (Cellerino 1999). In September 2019, powdery mildew was observed on the hybrid poplar Populus davidiana × P. alba var. pyramidalis, a fast-growing elite poplar cultivar widely planted in the northeast of China, in one poplar nursery room in the Northeast Forestry University in China (45.7266°N, 126.6380°E). Disease incidence during September and October was only 5 to 15% but gradually increased to 100% during November and December. The symptom of white circular powdery spots with diameters of up to 12 mm appeared on the upper surface of the mature leaves of poplar plants over 40 days old. Under nursery conditions (50 to 65% humidity, 20 to 25°C, and 16-h/8-h day/night cycles), the diameter of a mildew spot could develop from merely visible to 10 mm in 3 days. The mildew site was observed with a stereomicroscope (Leica DVM6S, Germany). A single fungal species demonstrating characteristics of the obligate pathogens Erysiphe spp. was observed. The conidiophores grew straight upward on the leaf surface until reaching 102 to 165 μm in length (n = 30). Then, even-looking, ellipse-shaped conidia were developed, forming a singular, curved string of up to tens of conidia, on top of each conidiophore. Conidia (n = 30) measured 29.4 to 35.1 × 18.1 to 21.0 μm. Appressoria were lobed or nipple-shaped and appeared in pairs or singular. The germ tubes were slightly curly unbranched tubes pointing at one direction near the long axis of the conidium. We carefully collected the mildew by scraping it off the upper surfaces of fresh diseased leaves with a scalpel and extracted the genomic DNA. The internal transcribed spacer rDNA region was amplified according to the method of Siahmard et al. (2017). The resulting nucleotide sequence (deposited in GenBank as MN998572) displayed 99.84% identity with that of Erysiphe adunca (KY653179.1). Hence, we identified the causal pathogen of this poplar powdery mildew as an E. adunca strain. Furthermore, an Mcm7 sequence (deposited as MN998573) and a Chs sequence (deposited as MN998574) were cloned according to the method of Ellingham et al. (2019). A voucher specimen and the sequence information have been deposited in the Northeast Forestry University Culture Collection (NECC) and named as NECCFP001. Pathogenicity was tested in the nursery, by merely placing healthy 40-day-old plants next to diseased plants (n = 10, with a 15 cm distance between plants), and by pressing the mildew sites of diseased leaves onto each mature leaf of the healthy plants (n = 10, also with 15 cm distance). The same symptoms appeared on heathy plants after 10 to 15 days, and 6 to 8 days, respectively. The induced mildew was confirmed morphologically to be NECCFP001 by microscopic examination. E. adunca occurs on aspen, willow, and Populus spp. throughout temperate regions of the Northern Hemisphere and forms fruiting bodies (chasmothecia) to overwinter (Horst 2001; Sinclair and Lyon 2005). However, chasmothecia were not observed in our case, suggesting no sexual morph under the nursery conditions. Incidents of powdery mildew on hybrid poplars caused by Phyllactinia populi had been reported in Jiangsu and Shandong provinces of China (Zhao et al. 2013). This is the first report of E. adunca causing poplar powdery mildew in Heilongjiang, China.

Pot host and media treatments towards kayu papi’s (Exocarpus latifolius R.Br) growth

Kayu papi or shrub sandalwood (Exocarpus latifolius R.Br.) is a hemiparasitic plant, member of Santalacea family which incorporated host plant on their nutrient absorption. Kayu papi is a fragrant wood that can mimic and perhaps substitute sandalwood (Santalum album Linn.). Many studies recorded that exocarpic acid derived from kayu papi is also beneficial as a tuberculosis remedy. However, the information on silvicultural techniques has only been investigated just a few times. This study aimed to examine the effect of host plants and media combination on kayu papi’s growth under the nursery condition. Kayu papi seedlings were planted with five different hosts and control (without host plant) on six different media. The parameters are the height and diameter of the seven-month kayu papi seedlings. The result indicates that host plants significantly affected kayu papi’s growth. The interaction between the host plant (Alternanthera spp.) and media combination latosol soil and manure also significantly promoted the height of kayu papi. While kayu papi grown in grumusol with Saorupus androgynous host showed the highest diameter on average. In conclusion, kayu papi seedlings indicate that host plant presence and particular media optimized their growth.

Biocontrol and Plant-Growth-Promoting Traits of Talaromyces apiculatus and Clonostachys rosea Consortium against Ganoderma Basal Stem Rot Disease of Oil Palm.

Basal stem rot (BSR) disease caused by Ganoderma boninense basidiomycetous fungus is the most economically important disease in oil palms in South East Asia. Unfortunately, there is no single most effective control measure available. Tremendous efforts have been directed in incorporation of environmentally friendly biocontrol approaches in minimizing BSR disease. This study investigated the performance of two potential biocontrol agents (BCAs), AAT0115 and AAB0114 strains recovered from oil palm on suppression of BSR in planta, and also assessed their plant-growth-promoting (PGP) performance. ITS rRNA-sequence phylogeny discriminated the two ascomycetous Talaromyces apiculatus (Ta) AT0115 and Clonostachys rosea (Cr) AAB0114 biocontrol species with PGP characteristics. In vitro studies have demonstrated both Ta and Cr are capable of reducing linear mycelial growth of G. boninense. Inoculation of individual Cr and Ta—as well as Cr+Ta consortium—induced a significant increment in leaf area and bole girth of oil-palm seedlings five months post-inoculation (MPI) under nursery conditions. At five months post-inoculation, shoot and root biomass, and nutrient contents (nitrogen, phosphorus, potassium, calcium, magnesium and boron) were significantly higher in Ta-inoculated seedlings compared to control treated with non-Ta-inoculated maize. Chlorophyll and carotenoids contents in rapidly growing oil-palm seedlings challenged with Cr, Ta or a combination of both were not negatively affected. Cr, Ta and Cr+Ta consortium treated seedlings had 4.9–60% BSR disease reduction compared to the untreated control. Co-inoculation of Cr and Ta resulted in increased BSR control efficiencies by 18–26% (compared with Cr only) and 48–55% (compared with Ta only). Collectively, Cr and Ta, either individually or in consortium showed potential as BSR biocontrol agents while also possess PGP traits in oil palm.

Printed Paper Waste as an Alternative Growing Medium Component to Produce Brassica Seedlings under Nursery Conditions

Significant quantities of paper waste (PW) have been accumulated in recent years and the reuse/recycling of PW is required due to environmental concerns. In the present study, printed PW was used as a peat (P) substitute in growing medium for the Brassica seedlings production, considering recycling, sustainable agriculture, and partly peat replacement. Seeds of cauliflower, broccoli, and cabbage were seeded in growing media made of 0–10–30–50% PW. The addition of PW improved the growing media pH and mineral content, reduced the media aeration, and affected seed emergence. The PW decreased plant growth and the effects were more pronounced at 50% PW. The PW ≥ 30% decreased stomatal conductance, while chlorophyll fluorescence and content of chlorophylls decreased with high PW ratio, negatively affecting the plant physiology. The PW decreased plant sodium and iron and increased potassium, calcium, magnesium, and copper content. The PW increased antioxidant activity to a certain degree for cauliflower and cabbage and resulted in no change for broccoli, while polyphenols increased in cabbage seedlings. The addition of PW did not cause cellular damage as both lipid peroxidation and hydrogen peroxide production remained at low levels, maintaining low levels on the antioxidant enzymes (catalase, superoxide dismutase, peroxidase) metabolism. The present study shows that low PW content can partially replace peat for Brassica seedling production under a sustainable agriculture and environmentally friendly scheme.

Inbreeding depression from selfing and mating among relatives of Hymenaea courbaril L

Inbreeding in trees can result in inbreeding depression (ID), which may affect adaptation and growth of individuals that originate from self-fertilization and mating among relatives. To investigate how inbreeding can affect seed, and seedling growth, we used microsatellite loci to determine the mating system of a Hymenaea courbaril population and assess traits of seeds and seedlings for the expression of ID. Ninety-nine adult trees were mapped and genotyped and seeds collected from eight trees in a forest fragment in Sao Paulo State, Brazil. Seed length and weight were measured and germinated seedlings that had been grown under nursery conditions were genotyped and measured for height and root collar diameter (RCD) at two-month intervals (7–17 months of age). Individual fixation index was estimated for each seedling, from which they were classified as originating from mating among unrelated parents (tu), related parents (tr), or selfing (s). This classification was confirmed using paternity analysis. Phenotypic means and ID of the measured traits were calculated for each determined s, tr, and s+tr group. Mating was not random due to the occurrence of self-fertilization (1.3%), mating among relatives (5%), and correlated mating (15.6%). Biparental inbreeding was attributed to significant spatial genetic structure up to 250 m. The mean fixation index within familieswas significantly higher in seedlings (0.184) than in adults (-0.035), indicating ID from seedling to adult stages. The ID varied among seed and seedling traits throughout the study and between mating groups. Self-fertilization resulted in greater ID for seed length (8.5%) and weight (21.3%) than for tr (<7%). The ID for height and RCD of selfed individuals tended to decrease over the course of the study. The values for ID for seedling height and RCD of the s group were greater (15.8–25.6% for both traits) than for the tr group (3.1–8.2%), with a total (s+tr) similar between height (7.6–9.4%) and RCD (8.1–10.5%). We recommend that seed collection is conducted across a large number of forest fragments in the region where the restoration is to be implemented, preferably in forests that are connected or as close as possible to other remnants, to mitigate the effects of ID in future generations. Seeds must be collected from a minimum of 47H. courbaril trees, respecting a minimum distance of 250 m between each tree to avoid collection of seeds from related individuals.

Use of Inoculator Bacteria to Promote Tuber melanosporum Root Colonization and Growth on Quercus faginea Saplings

Research Highlights: Mycorrhizal helper bacteria (MHB) promote mycorrhization processes and are commonly found in the mycorrhizosphere of fungi, such as the edible hypogeous fungus Tuber melanosporum Vittad. Background and Objectives: The effectiveness of MHB in promoting the mycorrhization process and the root development of Portuguese oak (Quercus faginea Lam.) seedlings destined for truffle plantations has not been determined. The main aim of this study was to shed light on the effect of bacterial inoculation on fungal root tip colonization and seedling root traits. Material and methods: We performed a co-inoculation trial using three bacteria naturally present in the T. melanosporum niche (i.e., Pseudomonas fluorescens, Pseudomonas putida, and Bacillus amyloliquefaciens) and two different bacterial inoculation times (one month and nine months after fungal inoculation) under glasshouse conditions. Results: Only P. fluorescens had a significant mycorrhizal promoter effect, increasing the truffle inoculation rates of root tips by more than 10% compared with seedlings that received non-bacterial inoculation treatments. Simultaneously, the co-inoculation of P. fluorescens with T. melanosporum improved seedling root growth parameters compared with those of seedlings that received non-bacterial inoculation treatments. The different bacterial inoculation times and applications of uninoculated bacterial growth media did not affect the root traits analyzed or the root mycorrhization rates. Conclusions: These results suggest that P. fluorescens bacteria have a potential commercial application as a treatment for truffle-inoculated seedlings to improve both seedling quality and mycorrhizal colonization under nursery conditions.

Morphological characteristics of Packham’s Triumph pear cultivar fruiting wood

Pear as a fruit species forms various categories of fruit-bearing branches during its life cycle. Depending on how many years it takes to form a young fruiting wood of pear cultivar from its meristem, there can be an annual, biennial, or perennial organogenesis cycle, which in the first place depends on cultivar’s genotype, the rootstock on which the cultivar is grafted, the applied agricultural techniques in nursery and other conditions. Knowledge of the individual pear cultivars organogenesis cycle is the basis for planning regular and stable yields. In order to determine the structure of a fruiting wood for an individual pear cultivar, it is necessary to make analyses on individual increment categories; what is developing from those increments in the following year. The morphological characteristics of annual increments are analysed (spurs, stems, and long shoots) of Packham’s Triumph pear cultivar, as well as the morphological characteristics of each category’s annual increment bourse-over-bourse, all with statistically significant difference between studied factors and factorial levels. Peckham’s Triumph had higher average length of long shoots in both examining years 2011 (53.63) and 2012 (45.33) and William's cultivar had the shorter ones.

Role of Trichoderma aggressivum f. europaeum as Plant-Growth Promoter in Horticulture

The main objective of this study was to determine the capacity of Trichoderma aggressivum f. europaeum to promote pepper and tomato seedling growth compared to that of T. saturnisporum, a species recently characterised as a biostimulant. Consequently, in vitro seed germination and seedling growth tests were performed under commercial plant nursery conditions. Additionally, the effects of different doses and a mixture of both species on seedling growth under plant nursery and subsequently under greenhouse conditions were determined. Furthermore, mass production of spores was determined in different substrates, and their siderophore and indole acetic acid production and phosphate (P) solubilisation capacity were also determined. Direct application of Trichoderma aggressivum f. europaeum to seeds in vitro neither increases the percentage of pepper and tomato seed germination nor improves their vigour index. However, substrate irrigation using different doses under commercial plant nursery conditions increases the quality of tomato and pepper seedlings. Tomato roots increased by 66.66% at doses of 106 spores per plant. Applying T. aggressivum f. europaeum or T. saturnisporum under plant nursery conditions added value to seedlings because their growth-promoting effect is maintained under greenhouse conditions up to three months after transplantation. The combined application of the two species had no beneficial effect in relation to that of the control. The present study demonstrates the biostimulant capacity of T. aggressivum f. europaeum in pepper and tomato plants under commercial plant nursery and greenhouse conditions.

Activity of Ailanthus altissima (Mill.) Swingle Extract as a Potential Bioherbicide for Sustainable Weed Management in Horticulture

The sustainable management of weeds is one of the main challenges in agriculture. Recent studies have demonstrated the potential of plant phytotoxins, such as ailanthone from Ailanthus altissima (Mill) Swingle, as bioherbicides. Since a complex extract may be more active than a single compound, we explored the phytotoxicity of A. altissima extracts obtained from the leaves, samaras, rachises, and secondary roots, and we evaluated their application potential for weed control in horticulture. The pre-emergence activity of all plant extracts was evaluated over varying concentrations on two indicator species (i.e., Lepidium sativum L. and Raphanus sativus L.) under controlled conditions. As the leaf extract was able to be generated in sufficient quantities, it was therefore further evaluated in glasshouse experiments with seven common weed species as indicators, as well as in a nursery production system for the cultivation of three horticultural crops (i.e., Salvia officinalis L., S. rosmarinus Schleid., and Dianthus caryophyllus L.). Following the application of the extract, the index of germination (IGe%), the index of biomass, and the density of weeds per pot were evaluated, along with the impact on crop growth and quality (i.e., plant growth index and leaf damage). Under controlled conditions, the extract from the secondary root was the most active in reducing the IGe%, with greater persistence across time in both indicator species. At 18 days following application, the lowest concentration of the leaf extract at 1.8 mg L−1 ailanthone reduced the IGe%by up to 15% and 45% in R. sativus and L. sativum, respectively. In R. sativus, all of the extract types affected the IGe%, but extract activity was greater in L. sativum. Under glasshouse conditions, leaf extracts containing 50 and 200 mg L−1 ailanthone showed strong inhibition (98%–99%) in the biomass of all treated indicator and weed species. Under nursery conditions, leaf extracts formulated at 100 and 200 mg L−1 ailanthone performed similarly, and no weeds were observed in any of the treated pots of S. officinalis and S. rosmarinus in the 60-day study period. Conversely, in the D. caryophyllus pots, an increase in the percentage of weed presence per pot was observed after 40 days. A reduction in the growth index and an increase in leaf phytotoxicity were observed during the cultivation experimentation, especially in S. officinalis when the extract was applied post-emergence to the crop canopy. Phytotoxicity was alleviated by the application of the extract directly to the soil or growth media. These results provide new insights into A. altissima extracts and their phytotoxicity to support their additional use as a sustainable solution for weed management in horticultural crops.

EFFECT OF PRUNING HEIGHT ON THE PRODUCTION OF ORTOTROPIC BUDS OR BRANCHES IN VIVERO CONDITIONS

Introduction: reforestation constitutes an imperative need for current generations; this guarantees the sustainability of wood for different purposes, while promoting healthy conditions for the environment; The scientific community redouble efforts to investigate techniques that make reforestation increasingly feasible and viable. Objective: To determine the effect of pruning height according to the number of buds in the production of orthotropic shoots or branches under nursery conditions. Methodology: experimental, descriptive and longitudinal study in which young plants of Juglans neotrópica were subjected to clonal forestry techniques by means of training prunings in mother plants Different statistics were used to identify the statistical significance of the changes in the appearance of shoots according to the pruning height and number of buds; These include the use of Pearson's chi-square, the correlation for continuity, the likelihood ratio and the linear association for linear. Results: the plants submitted to the A2S2 combination were the ones that showed the best yield in relation to the appearance of shoots. The plants subjected to the A1S1 and A2S2 combinations were the ones with the greatest delay in the appearance of shoots. Conclusions: there is no significant relationship between the appearance of shoots and the height of pruning according to the number of buds; therefore, it can be determined that the buds will appear interchangeably whether the pruning is performed at three or five buds.

Influence of Seed Source and Stratification on Germination and Growth of &lt;i&gt;Betula utilis&lt;/i&gt; D. Don under Temperate conditions in Kashmir Himalaya

The present study reports the influence of two seed sources (Special forest division Tangmarg and Bandipora forest division) and effect of different stratification treatments on germination and seedling growth parameters of Betula utilis in temperate region of Kashmir Himalaya. The seeds were collected in the month of September-October and subjected to six stratification durations of fifteen days interval at 4˚C ± 1˚C using completely randomized design. The seeds from Bandipora forest division performed better in terms of germination and seedling growth parameters giving maximum germination of (73.19%), seedling height (33.97 cm), collar diameter (5.42 mm), leaf area (97.03cm 2 /plant), number of leaves (11.67/seedling), seedling vigor index (25.98). Among six stratification treatments of 75 days (D 6 ) registered significantly higher germination (83.25%), plant height (43.08 cm), collar diameter (6.04 mm), seedling vigor index (36.05), leaf area (129.91 cm 2 / plant) and number of leaves (15.83/seedling). The study revealed that under nursery conditions, seeds from Bandipora forest division stratified for 75 days performed most promising treatment combination for obtaining better germination and seedling growth and hence recommended for mass multiplication of this species for conservation and management.

Impact of IBA and bio-inoculants on growth and rhizogenesis in pomegranate (Punica granatum)

The present experiment was conducted to study the effect of Indole butyric acid (IBA) as alone or in combination with synergetic bio-inoculants i.e. Azotobacter, phosphate solubilizing microorganisms (PSM) and Arbuscular Mycorrhizae (AM fungi) on rhizogenesis, vegetative growth parameters, biomass accumulation and nutrient uptake in hardwood cuttings of pomegranate (Punica granatum L.). Fifteen treatments excluding the control (water dipping) treated with IBA and inoculated with bio-inoculants alone or in different combinations were examined. All root and shoot related parameters were significantly improved in the cuttings treated with IBA and inoculated with bio-inoculants treatments. Maximum cuttings survival %, diameter of primary root, fresh and dry root weight, number of primary roots, plant height, number of branches, shoot diameter and shoots fresh weight was observed in cuttings treated with IBA and pre-inoculated with PSM + AM fungi followed by AM fungi + Azotobacter combinations. This study gives the future insight for exogenous applications of IBA with ecofriendly bio-inoculants in improving vegetative growth and increasing the production of healthy plants of horticultural crops under nursery conditions.

Preliminary survey on diseases of Mango (Mangifera indica) under nursery conditions

Mango saplings go through the many insect pests, fungal, bacterial diseases during nursery condition and these symptoms will persist till flowering and fruiting period and result in the huge economic losses. Majority mango saplings couldn’t reach upto flowering and fruiting stage it dies in the nursery conditions. This is major threat to the nursery owners because mango saplings having great demand all over the year, therefore buyers refuse to purchase diseased saplings. In the recent years the disease becomes severe in nursery plants, on young leaves, symptoms appear as irregular black necrotic spots on both sides. Pathogen present on the infected leaves, twig and fallen leaves serves as the major source of infection and spreads by rain splashed conidia. Survey was carried out to know the prevalence of diseases in nursery conditions for that Sanket Nursery Wakadi, Taluka Rahta was selected. There were 4 varieties of mango found in Sanket Nursery that were, Keshar, Payari, Mallika and Ratna. During the survey various fungal and insect pest diseases were observed. Anthracnose symptoms caused by Colletotrichum gloeosporioides, little leaf notcher, coconut scale, mango gall midge, white mango scale, stem blight, powdery mildew, hairy caterpillar etc. were found in large scale.

Comparação morfofisiológica de porta-enxertos clonais de seringueira cultivados em viveiro suspenso

O objetivo do trabalho foi caracterizar os parâmetros morfofisiológicos de porta-enxertos de seringueira provenientes de sementes dos clones GT1, PB235 e IAN873, cultivados em viveiro suspenso no município de Ilha Solteira- SP. O experimento foi desenvolvido em viveiro a céu aberto instalado na Faculdade de Engenharia - UNESP, Câmpus de Ilha Solteira- SP, durante o período de março/2018 a janeiro/2019. O delineamento experimental utilizado foi o de blocos ao acaso, em esquema fatorial de 3 x 5, sendo três porta-enxertos GT1, PB235 e IAN873 e cinco épocas de coleta de dados 60, 120, 180, 240 e 300 dias após transplantio (DAT), com três repetições de 10 mudas por parcela. Os porta-enxertos apresentaram variação significativa dos parâmetros fisiológicos e de crescimento ao longo do período experimental. O IAN873 destacou-se no incremento de diâmetro de caule, índice de qualidade de Dickson e teor relativo de clorofila, conforme apontou a leitura do índice SPAD-502. A taxa fotossintética de IAN873 foi baixa no início das avaliações (60 DAT), entretanto, elevou-se linearmente, igualando-se aos demais clones ao final dos 300 DAT. Durante o período de cultivo (300 DAT), sob condições de viveiro suspenso, o genótipo IAN873 demonstrou maior aptidão para uso como porta-enxerto.

Long-term heightened larval production in nursery-bred coral transplants

The ‘gardening coral reefs’ method is part of the approaches proposed for counteracting the substantial impacts of global climate change on the survival of coral reefs. It incorporates ecosystem engineering strategies for coral nursery farming and coral colonies out-planting. This study explores the reproductive output of three sets of nursery-grown Stylophora pistillata colonies along eight reproductive seasons following transplantation, as compared to that of native corals. When native and transplanted corals grew side by side in a disturbed environment, the nursery-grown transplants showed enhanced larval release (2.6–22.5 times more planulae/colony; multiyear average: 11.6±1.8 planulae/transplant vs. 1.5±0.3 planulae/native colony) with higher percentages of gravid colonies (91±2.1% transplants vs. 34±7.6% native colonies). The inherently enhanced larval production of transplants, maintained for such a long period of time post-transplantation, reveals a possible enduring impact of the nursery conditions on future fitness and ecological traits of transplants. This is further supported by the emerging documentation regarding the enhanced growth of corals under nursery conditions, which continues to be detected even years after transplantation was conducted on the natural reef. The above enhancement of coral reproduction can be harnessed as a human intervention tool for countering global climate change impacts.

Effect of water and salt stress on soil moisture status under nursery conditions

Soil is a natural body developed through pedogenic process, consisting of all necessary mineral and organic constituents who are require for plant growth and productivity. Therefore, any changes in the soil properties directly affect the plant growth status. In the present study, effect of artificially created abiotic stresses like drought, water logging, salinity, combined salinity + drought and salinity + water logging on the soil moisture of selected tropical forest tree species seedlings viz: Tectona grandis, Gmelina arborea, Dalbergia latifolia and Pongamia pinnata have been seen by performing pot culture experiment in factorial CRBD manner in TFRI nursery for one year duration. Transparent polythene bags were used filled with soil, sand and farm yard manure (FYM) in 2:1:1 ratio, keeping the weight of polybags fixed at 2 kg. The amount of water equal to the field capacity was given to each polybags. The moderate and severe drought conditions were created with the help of cumulative pan evaporation and permanent wilting point values. The artificial moderate and severe water logging conditions were created by perforating 8 periphery holes in the polybags below 6 cm and 3 cm from surface. 4dS/m, 8dS/m and 12dS/m sodium chloride salt dissolved water provided regularly for maintaining the salinity conditions. The salt doses combined with the illustrated drought and water logging way of treatments for generating combined salinity and drought & combined salinity and water logging conditions. The soil was analyses for general physicochemical characteristics so as to standardize the non-difference in the soil used along with the soil moisture by following gravimetric method. The soil moisture was measured initially on the start of experiment (August 2015) and then at six months intervals (February 2016 and August 2016). The data statistically analyses by using ANOVA table and CD values stated that there was the significant difference in the soil moisture readings of selected tree species. The maximum soil moisture was found in the severe waterlogged treatment, followed by moderate waterlogged, control and moderate drought and minimum in severe drought treatment irrespective of salt concentrations. Higher dose of salt concentration retains more moisture in the soil. The soil moisture holding capacity of different species remains unaffected under selected abiotic stresses.