Do Dipteryx alata Vogel seedlings recover the quality and the photosynthetic and antioxidant responses in the post-flooding?

Dipteryx alata Vogel is a tree species widely found in Cerrado, settling preferentially in well drained soils. Studies related to ecophysiology of D. alata may contribute to the decision making about using seedlings of this species in projects aimed at the recovery of degraded areas where seasonal flooding happens. This study aimed to assess the effects of flooding on photosynthetic and antioxidant metabolism and quality of D. alata seedlings cultivated or not under flooding during four assessment periods (0, 20, 40, and 60 days), followed by 100 days after the end of each assessment period (0+100, 20+100, 40+100, and 60+100 days), allowing verifying the potential for post-flooding recovery. Flooded plants showed lower photosynthetic efficiency than non-flooded plants, regardless of the periods of exposure. However, this efficiency was recovered in the post-flooding, with values similar to that of the non-flooded seedlings. Moreover, the damage to FV/FM was evidenced by an increase in the period of exposure to flooding, but recovery was also observed at this stage of the photosynthetic metabolism. Seedling quality decreased under flooding, not varying between periods of exposure, but remained lower although the increase observed in the post-flooding period, with no recovery after flooding. The occurrence of hypertrophied lenticels associated with physiological changes and an efficient antioxidant enzyme system might have contributed to the survival and recovery of these seedlings. Thus, this species is sensitive to flooding stress but capable of adjusting and recovering metabolic characteristics at 100 days after the suspension of the water stress, but with no recovery in seedling quality. Thus, we suggested plasticity under the cultivation condition and determined that the time of 100 days is not enough for the complete resumption of growth.

Yield and quality of basil depending on the method of growing seedlings

It is shown and proved then the first and mass seedling emergence 2 days faster due to cell 4х4 and 2,5 × 2,5 cm compere to cell 6 х 6 cm. Growth period from transplanting to budding of plants grown from cells 2,5 × 2,5 cm was 19 days only. It was shortest and 4 days earlier compere to plants from cell 6 × 6 cm or direct sowing. Longest growth period from transplanting to budding of plants was 30 days due to cassettes with cells 2,5 × 2,5 cm. Plants from seedlings longer formed first yield. It was 44 days which was 7 days longer compere with direct sowing. The most active growth of foliage of the Basil plant observed before transplanting to open soil due to cells 6х6 cm. The leaves surface was high. Plants which grown in cassettes with cells 4х4 and 6х6 cm had better biometric data. It was indicated then with increasing of substrate volume seedling quality indicators increased as well. Most active process of leaf surface growth in basil plants took place, which were grown in cassettes with a cell volume of 6 × 6 cm and before planting it in open ground, the leaf surface area was high. Regardless of the time of sowing seeds and planting seedlings in the open ground, the best biometric indicators were plants grown in cassettes with a cell volume of 6×6 cm, that is, with increasing food area per plant and seedling quality indicators increased. The longest peduncle (10,1 cm) had plants of second term of transplanting due to cells 4×4 and 6х6 cm . Higher yield had plants grown from cells 4 × 4 and 6 × 6 cm. Their yield was from 24,6 to 27,2 t/ha. Yield increase according to control was from 0,6 to 2,2 t/ha. Lowest yield shown plants which were grown in cassettes with volume of cells 2,5 × 2,5 cm from 20,9 to 24,3 t/ha.

Renewable organic waste as substrate conditioning for the production of Euterpe oleracea seedlings

Forest restoration has the premise of restoring degraded native vegetation to conditions prior to degradation. The objective of this work was to evaluate the production of seedlings of a native species from the Amazon biome (Euterpe oleracea) under different substrates. The experiment was carried out at the Federal University of Tocantins, using a completely randomized design, and a 5x 4 factorial scheme, with five substrates (babassu stem + soil, babassu stem + rice husk + soil, coconut fiber + soil, babassu stem + fiber coconut + rice husk + soil, commercial substrate + soil - control), four trial periods (50, 100, 150 and 200 days). The evaluated variables: plant height, stem diameter, shoot dry matter, root dry matter, total dry matter, seedling quality index, leaf area and absolute growth rate. The growth of assai seedlings was influenced by the different substrates, until the 150 days after transplanting the quality and development of the seedlings were the same, both for the treatments that used commercial substrate and for the treatments that used renewable materials in their composition. The treatment using babassu stem (T1) obtained better shoot dry matter, total dry matter and seedling quality index values, in addition to being a material found in abundance in the regions, making this treatment the most viable and recommended for the production of assai seedlings.

Utilization of nyamplung industrial waste for compost and the response to nyamplung seedlings growth and nitrogen uptake

The solid waste (dregs seed) of nyamplung (Calophyllum inophyllum) industry from seed pressing processes could be more than 50% of the dry seed weight. Nyamplung oil industry in Bantul (Yogyakarta) has been produced nyamplung oil 4-5 ton/month that produced dregs seed around 50-60%/ton nyamplung dry seeds. The accumulated waste has been piled up and immediately important to utilize it. This study aimed to determine (i) the effect of bioactivators with ameliorant material application and the interactions among treatments on nyamplung dregs compost quality, and (ii) the growth response, seedling quality index and nitrogen uptake on nyamplung seedlings with nyamplung dregs compost application. The study was arranged in Completely Randomized Design (CRD) factorial. Two bioactivators Prouponic Gb#1 and cattle rumen bio starter were used in the study. The bioactivators were combined by ameliorants (no ameliorant, dolomite, and rice husk ash) with 3 replicates for each treatment. Analyses of soil chemical properties were carried out on nyamplung dregs before and after the treatments applied including: pH, DHL, N Total, C/N ratio, P Total, K Total. Those characters were compared to SNI No.19-7030-2004 on compost quality standards. DHL, C/N ratio, the total N, P, and K met the criteria on SNI. Seedling growth characters (height, diameter, number of leaves) and seedling quality index varied between nyamplung dregs compost treatments and control up to 16 weeks observation. Nyamplung dregs compost application showed the highest N uptake on nyamplung seedlings compared to the controls. Nyamplung seedling quality index was highly influenced by the uptake of N nutrients in the shoots and the roots than by height character and diameter.

Studies on Seed Dormancy Breaking in Cucumber (Cucumis sativus L.) Variety Poinsett

Experiments were carried out to study the effect of chemicals in breaking the dormancy of cucumber. The study was conducted at the Department of Vegetable Science, Horticultural College and Research Institute, Coimbatore during 2017-2018. The seeds of cucumber variety Poinsett were treated with various chemicals immediately after harvest to standardize the best dormancy breaking treatment. The design of the experiment was Factorial Randomised Block Design with two replications. The seeds were treated with the chemicals for 12 hrs and 24 hours duration. The germination test was conducted. Observations on seed and seedling quality parameters viz., speed of germination, and germination percent, vigor index I and vigor index II were recorded. At 12 hours duration, the highest speed of germination (23.29) was recorded in T2 (GA3150 ppm) whereas the highest germination percentage (92) was recorded in T8 (Ethrel150 ppm). At 24 hours duration, the highest speed of germination (30.77) and the highest germination percentage (86) was observed in T12 (KNO3500 ppm). At 12 hours duration, the highest Vigor Index I (2800.16) was recorded in T9 (Ethrel 500 ppm) while the vigor Index II was the highest (12.19) in T8 (Ethrel150 ppm). At 24 hours duration, the highest Vigor Index I (2349.28) was observed in T10 (Ethrel 1000 ppm) while the vigor Index II was the highest (14.066) in T11 (KNO3150 ppm).

Arbuscular mycorrhizae alleviate water deficit in Dipteryx alata Vogel: seedling quality and resilience

Dipteryx alata Vogel (Fabaceae) is a fruit tree species native to the Cerrado with ecological and economic potential. However, water deficit can be a limiting factor to the initial growth of this species, requiring knowledge on technologies that can alleviate this stressful effect. We hypothesized that inoculation with arbuscular mycorrhizae fungi contributes to stress mitigation during and after water deficit. D. alata seedlings were subjected to two water regimes (control: seedlings irrigated daily; and water deficit: irrigation suspension); associated with inoculation with arbuscular mycorrhizal fungi (AMF): AM- = without inoculation; AM+ = inoculation with Rhizophagus clarum; and three evaluation periods: T0 - time zero; F0 - zero photosynthesis (seven days of water restriction); REC - recovery (100 days). Water deficit impaired water relations, decreasing the quality of D. alata seedlings. AM+ seedlings showed higher relative water content (RWC), leaf area ratio, chlorophyll index, and Rubisco carboxylation capacity (A/Ci), which helped in photosynthetic metabolism. Inoculation with R. clarum alleviated the impact of stress on water use efficiency, water potential, RWC, and A/Ci in REC. Inoculation with AMF is a promising management technique in the production of D. alata seedlings for increasing seedling quality and resilience to water deficit.