Hydrogels Improve Plant Growth in Mars Analog Conditions

Sustainable human settlement on Mars will require in situ resource utilization (ISRU), the collection and utilization of Mars-based resources, including notably water and a substrate for food production. Plants will be fundamental components of future human missions to Mars, and the question of whether Mars soils can support plant growth is still open. Moreover, plant cultivation may suffer from the lack of in situ liquid water, which might constitute one of the biggest challenges for ISRU-based food production on Mars. Enhancing the crop yield with less water input and improving water utilization by plants are thus chief concern for sustainable ISRU food production. Hydrogels are polymers able to absorb large quantity of water and to increase soil water retention, plant establishment and growth. This work reports on the short-term assessment of plant growth in Mars soil analogs supplemented with hydrogels. Soil analogs consisted of sand and clay-rich material, with low organic matter content and alkaline pH. Soils were supplemented with 10% (w/w) potting medium and were sampled in Utah desert, in the vicinity of the Mars Desert Research Station, surrounded by soils sharing similarities in mineralogical and chemical composition to Martian soils. Height and dry biomass of spearmint (Mentha spicata) were compared under various irrigation frequencies, and seed germination of radish (Raphanus sativus) were monitored. Under limited irrigation, results indicate that the soil analogs were less capable of supporting plant growth as a comparison to potting medium. The effects of hydrogel supplementation were significant under limited irrigation and led to spearmint heights increased by 3 and 6% in clay- and sand-containing soils, respectively. Similarly, hydrogel supplementation resulted in spearmint mass increased by 110% in clay-containing soils and 78% in sand-containing soils. Additionally, while radish seeds failed to germinate in soil analogs, hydrogel supplementation allows for the germination of 27% of seeds, indicating that hydrogels might help loosening dense media with low water retention. Collectively, the results suggest that supplementation with hydrogel and plant growth substrate could help plants cope with limited irrigation and poor alkaline Mars soil analogs, and are discussed in the context of strategies for ISRU-based off-world colonization.

Date palm compost versus peat and perlite: a comparative study on germination and plant development of muskmelon and tomato

This research was carried out in the experimental site of the Arid and Oasian cultures Laboratory of the Institute of Arid Regions, Medenine, Tunisia. It aims at studying the effects of compost on seed germination patterns, seedling growth, and plant development of muskmelon and tomato under greenhouse conditions. Three growth media were used: compost of date palm wastes and two reference media (peat and perlite). The results showed that compost presented a promising threshold of both maturity and stability, which is related to its neutral pH, C : N ratio, greater humic acid vs fulvic acid, and low values of chlorophyll-type compounds. Seeds of muskmelon and tomato germinated at varying liquid compost extract concentrations and muskmelon reached higher germination index values even at the pure extract solution (100%). Moreover, seeds of both species germinated relatively faster in peat than in compost and an overall delay in germination was observed, with a more pronounced reduction on tomato germination percentage. Produced seedlings have attained a similar vigour index among media (p <0.05). Compost of date palm was more suitable for muskmelon stem elongation and leaf-enlarging capacity than perlite. However, the gustative quality of fruits was not significantly affected by the medium-types. Thus, it is concluded the promoising effect of compost of date palm as potting medium and substrate in soilless culture under greenhouse conditions unless a pertinent choice of cultures.

Compost Functions as Effective Replacement for Peat-Based Potting Media in Organic Greenhouse Transplant Production

Commercial horticulture in many regions of the world depends upon Sphagnum peat as a potting-media substrate, but extracting peat has serious environmental consequences. Composts may be able to serve as effective substitutes for peat and offer potential environmental advantages. The suitability of compost as potting media depends upon the raw materials as well as processing methods used. This study includes two related experiments—one with beet (Beta vulgaris L.) and the other with tomato (Solanum lycopersicum L.)—aimed at assessing the potential viability of farm-produced, food-residuals compost as a replacement for peat-based potting media in the production of organic vegetable transplants. The experiments were conducted in 2021 on the Berea College Farm in Kentucky, USA, a USDA certified organic farm. The results indicated that potting media composed of 75% to 100% compost performed as well as fertilized, peat-based growing media for plant growth. Further, although weeds were present in the compost, weed pressure was not severe enough to adversely affect crop growth. Thus, sterilization of compost, which did eliminate weeds in the compost, was not deemed necessary for using the compost as a partial or complete potting medium. Compost pasteurization was also assessed but was ineffective in destroying weed seeds.

Micropropagation of Citrus indica Tanaka using Shoot tips from Mature Trees

A study was conducted to standardize a protocol for in-vitro direct regeneration and mass multiplication of Citrus indica Tanaka using shoot tip explants excised from mature trees. Shoot tips were inoculated in MS medium supplemented with varying concentrations and combinations of cytokinins and auxins. MS media when fortified with BAP 0.5 mg/l and 0.5 mg/l BAP + 1.0 mg/l Kn were found to be the best treatments for shoot initiation while MS supplemented with 1 mg/l IBA; 0.5 mg/l NAA + 0.5 mg/l IBA and 0.5 mg/l NAA + 0.5 mg/l IAA were the best treatments for root induction. Among the different media used for hardening, 100 % survivability was obtained when plantlets were hardened using vermicompost as the potting medium. Subsequently, these plantlets were transferred to larger pots and acclimatization was achieved gradually in outdoor conditions. Plant Tissue Cult. & Biotech. 31(1): 13-23, 2021 (June)

Responses of Fig Cuttings (Ficus Carica) to Different Sowing Dates and Potting Media under Agro-Climatic Conditions of Haripur

Background: Fig belongs to tropical and subtropical climates, and Haripur district being a subtropical area have great potential for successful commercial cultivation of figs. The most common method of fig propagation is by hardwood cutting, which is an easy and economical way of propagation. But lack of knowledge regarding suitable date of cutting collection and sowing and selection of appropriate potting medium severely limits the production of fig on a commercial scale. Objectives: Current study was undertaken in order to identify suitable collecting dates of fig cuttings and to develop a suitable potting media for the successful establishment of fig cutting. Methodology: The study was comprised of four different potting media i.e. Soil, Farmyard or Manure (FYM), Compost, Soil+FYM+Compost (1:1:1) and cuttings of fig cultivar Sawari were collected and sown on two different dates i.e. 1st January and 15th January in polyethene bags of uniform size. The experiment was laid in Complete Randomized Design (CRD). Results: Results revealed that maximum Length of the root (9.8 cm), Shoot thickness (1.4 cm) and Number of leaves (4.1) were noted in FYM, whereas maximum days to Sprouting (18.5) and Survival percentage (82.3%) were noted in Soil+FYM+Compost (1:1:1). Whereas fig cutting sown on 15th January showed maximum Days to sprouting (18.8), Length of the root (9.4 cm), Survival percentage (87.1%), Shoot thickness (1.8cm) and Number of leaves (4.6). Conclusion: It can be concluded that FYM and 15th January showed highest values of studied parameters.

Use of Recycled Potting Medium for Containerized Production of Squash

Vegetable growers are keen on cost-cutting measures to increase profitability. Containerized vegetable production can be done in a shade-house or garden, and it often requires commercial potting media. Although expensive, potting media are lightweight and provide high water- and nutrient-holding capacities, and thus they are widely used by growers. Growers often discard or compost the potting media after a single season due to issues such as diseases, pests, and weeds. However, old potting media could be reused for containerized production if appropriately sterilized and amended with fertilizer salts. The current study was conducted to determine the feasibility of using sterilized recycled potting medium amended with fertilizer salts for containerized production of squash. This new 4-page publication of the UF/IFAS Horticultural Sciences Department was written by Marie Dorval, Riphine Mainviel, Vincent Michael, Yuqing Fu, Bala Rathinasabapathi, and Geoffrey Meru.https://edis.ifas.ufl.edu/hs1404

Effect of different potting mixtures on growth and flowering characters of Chrysanthemum cv. Haldighati

This study evaluates the effect of different potting mixtures on growth and flowering of Chrysanthemum cv. Haldighati. The experiment was carried out at Agriculture Farm, School of Agricultural Sciences & Technology, RIMT University, Mandi Gobindgarh, Punjab, India. Different treatment methods include mixing sand, soil, cocopeat, ver powder, farmland fertilizer and perlite in equal proportions. Statistical analysis of the data show that the medium combination has a significant influence on the control value. The results show that the overall performance of Chrysanthemum is better in the medium with T7 (Perlite + FYM + garden soil (2:1:1)), but T5 is Vermicompost + FYM + Garden soil (2:1:1) has the highest main branches of each plant and the number of sub-branches per plant, the number of ray florets per flower, the length of ray florets and the width of ray florets. According to the obtained results, it can be concluded that compared with perlite Chrysanthemum, the potting medium treatment combination consisting of Perlite + FYM + garden soil (2:1:1) is most suitable for producing Chrysanthemums. It has been found that the light growth medium is more suitable for plant morphological development and continuous high-quality flower production.

Effect of seed treatments and potting medium on seed germination parameters in threatened Stereospermum suaveolens (Roxb.) DC. – A dashmool species

An experiment was conducted to investigate the effect of different seed treatment and potting media on germination percentage and associate parameters in Stereospermum suaveolens, a threatened dashmool species during May, 2019 at Silviculture Nursery of Tropical Forest Research Institute, Jabalpur (Madhya Pradesh). Experimental treatments comprised of twenty treatment combinations consisting of four different seed treatment and five growth mediums. Data on daily seed germination was recorded and used for estimation of final germination percentage (FGP), mean germination time (MGT), coefficient of velocity of germination (CVG), germination rate index (GRI), time spread of germination (TSG), energy period (EP) and peak value of mean germination (PVMG). Critical perusal of analysis revealed that treatment combination ‘Sand + Hot Water’ was resulted in positive effect on all the characters studied and could be used for mass raising of seedlings of S. suaveolens.

Design and Fabrication of Coir Pith briquetting Machine

Small scale industries play a major role in the economic development of India, to enhance its growth and to effectively utilize the renewable energy, waste products to be reused one such product is coir pith. Coir Pith is the spongy, peat like residue from the processing of coconut husk and it is pressed to required thickness in order to make it as pith briquettes. Coir is mainly used in exporting and in agricultural field, as it is good absorbent of the water. It maintains the moisture content of the pith to enhance the quality of the product. The purpose of this project work is to design and fabricate “COIR PITH PREOUETTING MACHINE” for maintaining the growth of the plants in the potting medium with less consumption of electricity and labors.