Effect of Plant Spacing and Harvest Interval on the Growth Parameters of Moringa oleifera Lam (Periyakulam-1) in Sokoto (Semi-Arid Environment)

Moringa is a typical representative of multi-purpose tropical tree crop due to the high nutritional value, it is an important source for food to many communities and provides raw materials for animal feed industries. This study investigates the influence of plant densities (15 x 15 cm, 15 x 20 cm, 20 x 20 cm, and 20 x 30 cm) and four (4) harvesting intervals (HI) of 2, 4, 6 and 8 weeks was laid out using Randomized Complete Block Design (RCBD) replicated three times. Data on silvicultural practices were collected and six (6) plants were randomly selected for harvest from each plot which were subsequently separated into leaves, stems and twigs. Fresh and air-dried weights were recorded for analysis. Analysis of Variance (ANOVA) was used for data analysis Duncan’s Multiple Range Test was used to separate the means. Results of the present study show non-significant effects of plant density (p>0.05) between treatments. However, greater number of branches, leaves, height and biomass accumulation was recorded at 8 weeks harvesting interval. A significant interaction effects were recorded between spacing and HI.

Pengaruh Interval Waktu Panen terhadap Produksi Biomassa Chlorella sp. dan Melosira sp. untuk Penangkapan Karbon secara Biologi

ABSTRACTThe aim of this study was to determine the effect of harvesting frequency on the growth of Chlorella sp. and Melosira sp. and on their total biomass production to estimate the amount of carbon fixed during 11 days of culture. Chlorella sp. and Melosira sp. were cultured in f/2 medium in seawater. The biomass was harvested at harvesting intervals of every day (P1), every 2 days (P2) and every 3 days (P3). The biomass of Chlorella sp. harvested at P1, P2 and P3 were 0,49 g/L, 0,43 g/L, and 0,35 g/L, respectively. The highest total biomass production of Chlorella sp. after 11 days of cultivation was obtained from P1 (8,80 g/L), while total biomass production at P2 and P3 were 52% (4,59 g/L) and 30% (3,25 g/L) of that P1, respectively. The biomass harvested at P1, P2 and P3 were 2,41 g/L, 1,40 g/L, and 1,63 g/L. Total biomass production of Melosira sp. during 11 days of cultivation for P1, P2 and P3 were 34,56 g/L, 17,33 g/L, 11,20 g/L, respectively. Our results showed that the highest total biomass production of both Chlorella sp. and Melosira sp. were obtained from harvesting every day. The estimated value of CO2 bio-fixation based on biomass production by Chlorella sp. and Melosira sp. were 1,5 g/L/day and 5,9 g/L/day, respectively.Keywords: biomass, microalgae, Chlorella sp, harvesting interval, Melosira sp, carbon capture ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh interval waktu panen biomassa mikroalga terhadap pertumbuhan Chlorella sp. dan Melosira sp., dan perolehan total biomassanya untuk estimasi CO2 yang difiksasi selama kultur 11 hari. Chlorella sp. dan Melosira sp. dikultivasi dalam media air laut yang berisi nutrien f/2. Biomassa mikroalga dipanen dengan interval waktu panen tiap hari (P1), tiap 2 hari (P2) dan tiap 3 hari (P3). Sebagai kontrol (P0), biomassa mikroalga dipanen hanya pada akhir percobaan yaitu di hari ke-11. Kelimpahan sel kultur Chlorella sp. pada perlakuan P1, P2 and P3 masing-masing adalah 2,38x106 sel/mL, 2x106 sel/mL,1,5x106 sel/mL, sedangkan total biomassa yang diperoleh masing-masing adalah 0,49 g/L, 0,43 g/L, dan 0,35 g/L. Total produksi biomassa Chlorella sp. tertinggi yang diperoleh selama 11 hari kultivasi dijumpai pada perlakuan P1 (8,80 g/L), sedangkan total produksi biomassa pada P2 dan P3 hanya 52% (4,59 g/L) dan 30% (3,25 g/L) dari total biomassa P1. Kelimpahan sel Melosira sp. yang dipanen dengan interval P1, P2 dan P3 masing-masing adalah 4,28x106 sel/mL, 2,22x106 sel/mL, dan 2,36x106 sel/mL, dan biomassa yang diperoleh masing-masing adalah 2,41 g/L, 1,40 g/L, dan 1,63 g/L. Total produksi biomassa Melosira sp. yang diperoleh selama 11 hari kultivasi untuk perlakuan P1, P2 dan P3 masing-masing adalah 34,56 g/L,17,33 g/L, dan 11,20 g/L. Hasil percobaan ini menunjukkan bahwa total produksi biomassa tertinggi pada Chlorella sp. dan Melosira sp.dijumpai pada kultur yang dipanen setiap hari. Estimasi serapan karbon berdasarkan biomasa yang dihasilkan oleh Chlorella sp dan Melosira sp. masing-masing adalah 1,5 g/L/hari dan 5,9 g/L/hari.Kata kunci: biomassa, mikroalga, Chlorella sp., interval panen, Melosira sp., penangkapan karbon

Sod Harvesting Intervals of Four Warm-Season Turfgrasses for Halosulfuron and Sulfentrazone

Sedges are problematic weeds that reduce quality of turfgrass sod, and herbicides may be needed for control prior to harvesting. The objective of this research was to evaluate application timing of halosulfuron and sulfentrazone on sod quality, tensile strength, and postharvest rooting of four warm-season turfgrasses. Bermudagrass injury from herbicides was minimal (< 10%), but injury to centipedegrass, St. Augustinegrass, and zoysiagrass was detected before harvesting and generally increased with sulfentrazone rate from 0.21 to 0.84 kg ai ha−1. Sod tensile strength was not reduced from the nontreated for bermudagrass and centipedegrass treated with herbicides, but tensile strength was reduced 15 and 22% following herbicide applications 1 wk before harvesting (WBH) St. Augustinegrass and zoysiagrass, respectively. Sulfentrazone at 0.84 kg ha−1reduced zoysiagrass tensile strength 20% from the nontreated, but other treatments did not reduce measurements. Turfgrass injury from halosulfuron was negligible on all species, and treatments did not affect sod tensile strength of the four species. Treatments did not affect root mass of any species at 4 wk after sod transplanting. Sod quality after transplanting was reduced from the nontreated on several dates for centipedegrass and St. Augustinegrass when treated with sulfentrazone 1 and 2 WBH, and zoysiagrass quality was reduced from treatments 4 WBH. Bermudagrass quality after transplanting was not reduced from the nontreated by any herbicides. Results suggest sod harvesting should be delayed 1, > 2, > 2, and ≥ 4 weeks after sulfentrazone applications at labeled rates for bermudagrass, centipedegrass, St. Augustinegrass, and zoysiagrass, respectively. Sod harvesting should be delayed 1, 2, ≥ 4, and 2 wk after halosulfuron treatments at 0.07 kg ai ha−1for bermudagrass, centipedegrass, St. Augustinegrass, and zoysiagrass, respectively.

Effect of harvesting time on phytomass production and essential oil yield in "alecrim-pimenta" (Lippia sidoides Cham.)

The aim of this study was to evaluate fresh and dry mass, as well as essential oil yield, in Lippia sidoides cultivated in the north of Minas Gerais State, Brazil. The experimental design was in randomized blocks, with five treatments and four replicates. Treatments consisted of the following harvesting intervals: 120, 180, 240, 300 and 360 days after transplanting. Measurements on each harvesting included plant height, stem base diameter, leaf, stem and shoot fresh matter yield, and shoot dry matter yield, besides essential oil content and yield per plant. The highest essential oil content was detected at 180 days, whereas the highest dry matter production was observed at 390 days. Essential oil yield per plant was 2.34±1.15 g and productivity was 124.8 kg ha-1. Thus, harvesting at 180 days is recommended.

EFFECT OF TIME INTERVAL BETWEEN POD SET AND HARVESTING ON THE MATURITY AND SEED QUALITY OF FLUTED PUMPKIN

A two-year study considered the effect of pod harvesting intervals of 3, 5, 7, 9, 11 or 20 weeks after pod set (WAPS) on the relationship between the physical condition of the pods, seed maturation and quality in fluted pumpkin (Telfairia occidentalis). Pod characteristics, such as the intensity of bloom wax on the pod and stiffness of the pod ridges, showed perfect linearity and correlation with the age of the pod, whereas changes in seed quality factors – germination, dry matter, oil and protein concentrations were curvilinearly associated with the time of pod harvest. Thus, seed quality factors increased steadily up to nine WAPS then declined. The point at nine WAPS defined as physiological maturity for fluted pumpkin seed and approximate visible indications of this point in the field were fairly stiff pod ridge condition and fading of bloom wax.