Allelopathic Effects of Essential Oils on Seed Germination of Barley and Wheat

In this study, we evaluated the allelopathic effects of essential oils (EOs) from six different plant species, namely, lavender (Lavandula angustifolia), hyssop (Hyssopus officinalis), English thyme (Thymus vulgaris), lovage (Levisticum officinale), costmary (Chrysanthemum balsamita), and cumin (Cuminum cyminum), on seed germination and seedling growth of barley (Hordeum vulgare) and wheat (Triticum aestivum). The main constituents of the EOs of L. angustifolia were 47.0% linalool acetate and 28.4% linalool; H. officinalis’ main constituents were 39.8% cis-pinocamphone, 9.8% trans-pinocamphone, 11.4% β-pinene, and 7.5% β-phellandrene; T. vulgaris’ were 38.2% para-cymene, 25.6% thymol, and 13.6% γ-terpinene; L. officinale’s were 64.8% α-terpinyl acetate and 14.7% β-phellandrene; C. balsamita’s were 43.7% camphor, 32.4% trans-thujone, and 11.6% camphene; C. cyminum’s were 49.6% cumin aldehyde, 10.4% para-cymene, 11.6% α-terpinen-7-al, and 9.1% β-pinene. All six EOs exhibited an allelopathic effect and suppressed the seed germination and seedling development of wheat and barley; however, the concentrations that exhibited a suppressing effect were different among the plants. C. cyminum EO completely suppressed both barley and wheat germination at 10-, 30-, and 90-µL application rates, making it the most effective treatment among the tested EOs. C. balsamita’s and H. officinalis’ EOs at 30 and 90 µL application rates completely suppressed barley and wheat radicles per seed, radicle length (mm), seedling height (mm), and germination (%). L. angustifolia’s EOs at 30- and 90-µL and T. vulgaris’ EO at 90 µL application rates also completely suppressed barley and wheat radicles per seed, radicle length (mm), seedling height (mm), and germination (%). C. balsamita’s, H. officinalis’, L. angustifolia’s, and T. vulgaris’ EOs at a 10 µL application rate reduced barley radicle length, seedling height, and % germination relative to the control. Wheat seed germination % was completely suppressed by the application of L. angustifolia’s and T. vulgaris’ EOs at 30 and 90 µL, while T. vulgaris’ EO at 10 µL rate reduced the germination relative to the control. Interestingly, C. balsamita and H. officinalis at 10 µL did not reduce wheat germination; however, they did reduce the number of radicles per seed, radicle length (mm), seedling height (mm), germination (%), and vigor index. Furthermore, L. officinale’s EO reduced the measured indices (radicles per seed, radicle length, seedling height, and vigor index) at the 10, 30, and 90 µL application rates relative to the non-treated control; however, none of the application rates of L. officinale’s EO had a suppression effect on wheat germination. This study demonstrated the allelopathic effects of the EOs of six different herbal plant species on seed germination of barley and winter wheat. The results can be utilized in the development of commercial products for controlling pre-harvest sprouting of wheat and barley. Further research is needed to verify the results under field conditions.

Effects of Sand Burial Depth on Xanthium Spinosum Seed Germination and Seedling Growth

different sand burial depths on seed germination, seedling emergence, growth and biomass allocation were studied to provide a scientific basis for further control of X. spinosum. Six sand burial depths (1, 2, 3, 5, 7 and 9 cm) were established to explore the response of X. spinosum seed germination and seedling growth to sand burial. The first emergence time, peak emergence time, emergence rate, seedling growth height, biomass and biomass distribution of X. spinosum seeds had significant effects at different sand burial depths (P < 0.05). The X. spinosum seeds had the highest emergence rate (71.5%) at 1 cm sand burial and the maximum seedling height (7.1 cm). As sand burial depth increased, the emergence rate and seedling height gradually decreased, and the emergence rate (12.25%) and seedling height (2.9 cm) were lowest at 9 cm sand burial. The root length at 9 cm depth (13.6 cm) was significantly higher than that at other sand depths (P < 0.05). The sand burial depth affected the biomass accumulation and distribution of X. spinosum. As sand burial depth increased, the root biomass and rhizome ratio increased, and the most deeply buried seedlings allocated more biomass for root growth. The optimal sand burial depth for seed germination and seedling growth of X. spinosum was 1–3 cm, and high burial depth (5–9 cm) was not conducive to the germination and growth of X. spinosum seedlings. For prevention and control of X. spinosum, we suggest deeply ploughing crops before sowing to ensure X. spinosum seeds are ploughed into a deep soil layer.

UJI FORMULA BIOFUNGISIDA TABLET BERBAHAN AKTIF KONSORSIUM Trichoderma virens ENDOFIT DAN MIKORIZA INDIGENOUS TERHADAP PENYAKIT JAP PADA BIBIT KARET

The objective of this research is to determine the effect of biofungicide tablets with active ingredient of the consortium consisted Trichoderma virens endophyte and mycorrhiza indigenous and to get the best formula to control the JAP disease on rubber plant. The research was carried out experimentally by using a completely randomized design (RAL), consisting of 6 treatments and 4 replications in order to obtain 24 experimental units. Each experimental unit consisted of two seeds, so there were 48 rubber seeds. The treatments seed were: F1 (15 ml T. virens endophyte), F2 (15 gr inokulan mychorrhiza), F3 (15 ml T. virens endophyte + 15 gr inokulan mychorrhiza + 100 gr palm fronds powder + 25 gr zeolite + 25 gr tapioca powder), F4 (15 ml T. virens endophyte + 15 gr inokulan mychorrhiza + 100 gr sago powder + 25 gr sago dregs + 25 gr tapioca powder), F5 (15 gr inokulan mychorrhiza + 100 gr solid + 25 gr zeolite + 25 gr tapioca powder) and F6 (15 ml T. virens endophyte + 100 gr cocoa shells powder + 25 gr sago dregs + 25 gr tapioca powder). Parameter observerd were initial symptoms on seedlings, intensity of disease, addition of plant height, stem diameter, and weight of dry seedlings. The data obtained were analyzed for variance followed by further tests of honest real difference (BNJ) at the 5% level. The results indicated that F3 (15 ml T. virens endophyte + 15 gr inokulan mychorrhiza + 100 gr palm fronds powder + 25 gr zeolite + 25 gr tapioca powder) was the best formula in controlling JAP with initial symptoms of infection of 24,50 days with the seedling height was 69,46 cm, stem diameter and dry weight were 6,60 cm and 103,62 gr respectively.

Irrigation frequency and soil type influence germination and early growth of quinoa (Chenopodium quinoa Willd).

The adoption of quinoa as a potential food crop in semi-arid Zimbabwe is threatened by poor seed establishment. A 4 x 3 factorial experiment arranged in a completely randomised design (CRD) was carried out to establish the effects of irrigation frequencies and different soil types on germination and early growth of quinoa. Three soil types (sand, loam, and clay) and four irrigation frequencies (after every 1, 2, 3, and 4 days) were used. Measurements taken included days to 50% emergence, germination percentage, mean germination time, germination rate index, coefficient velocity of germination, seedling height, final crop stand, and root density. Analysis of variance (ANOVA) was done using GenStat 18th Edition and mean separation was done using the Least Significant Difference (LSD) at a 5% significance level. There was an interaction between irrigation frequency and soil type on days to 50% emergence (p<0.05), germination percentage (p<0.05), germination rate index (p<0.05), seedling height (p<0.05), root length density (p<0.05), seedling crop stand (p<0.05). Sandy soil irrigated on 1-day intervals recorded the highest germination percentage (96.7%), while clay irrigated on 3-day intervals recorded the lowest (41.7%) final germination percentage respectively. Seeds planted in sand and clay recorded the shortest (3.25) and longest (4.5) mean germination time (days) respectively. Loamy and sandy soils irrigated on 3-day intervals and 1-day intervals recorded the lowest (29.4%) and highest (70.4%) germination rate index respectively. Loam soil irrigated on 1-day and 4-day intervals recorded the highest (16.37 cm) and shortest (9.3 cm) seedling height. Loam soil irrigated on 2-day and sandy soil irrigated on 3-day intervals recorded the lowest (3.07 cm/cm3) and the highest (21.23 cm/cm3) root length densities respectively. Sand irrigated on 1-day intervals recorded the highest (85%) crop stand. Findings concluded and recommended planting and frequently irrigating quinoa in sandy soils for better crop establishment.

The Effect of Seed Size on Germination and Seedling Growth in Sweet Chestnut (Castanea sativa Mill.)

The quantity and quality of seedlings in the nursery has an impact on the success of re-establishment and later growth. High germination rates enable a sufficient number of seedlings, and their quality is assessed using a number of parameters, including seedling height and root collar diameter. These parameters are influenced in some species by seed size, but the correlation between them is species-specific. The model species in this research was sweet chestnut (Castanea sativa Mill.), and seeds from 12 populations from two distinct biogeographical regions of Croatia were collected. We examined the influence of seed size on four parameters: germination rate, seedling height, root collar diameter and sturdiness quotient. Seed size has been shown to have a positive influence on both seedling height and root collar diameter, whereas no such correlation was noted for germination rate and sturdiness quotient. Significant differences in nut size and seedling growth parameters were found between the Mediterranean and continental populations, with higher values observed in the coastal Mediterranean populations. We concluded that seed origin and seed size have a significant impact on seedling growth and are important factors to consider when choosing seed material. Further nursery operations should consider seed origin and local environmental conditions when choosing seedlings for reforestation efforts and general forest operations.

Saturação por bases e doses de fósforo na produção de mudas de ipê rosa (Handroanthus impetiginosa)

O ipê rosa (Handroanthus impetiginosa) é uma espécie arbórea nativa do Brasil usada na ornamentação e recomposição florestal. Para garantir que mudas de qualidade sejam utilizadas em qualquer finalidade, para a qual se emprega essa espécie, deve-se conhecer mais a respeito das suas exigências nutricionais. Diante disso, um experimento foi realizado com o objetivo de avaliar a saturação por bases e diferentes níveis de fósforo (P) na produção de mudas do ipê rosa. O experimento foi conduzido em delineamento inteiramente casualizado com nove tratamentos e cinco repetições: T0 (100% substrato comercial); T1 (V50% de saturação por bases); T2 (V60% de saturação por bases); T3 (V50% de saturação por bases + 50 kg ha-1 de P2O5); T4 (V50% de saturação por bases + 100 kg ha-1 de P2O5); T5 (V50% de saturação por bases + 150 kg ha-1 de P2O5); T6 (V60% de saturação por bases + 50 kg ha-1 de P2O5); T7 (V60% de saturação por bases + 100 kg ha-1 de P2O5); T8 (V60% de saturação por bases + 150 kg ha-1 de P2O5). As características morfológicas foram avaliadas ao final de 90 dias. A saturação por bases e a adubação fosfatada não influenciaram no crescimento em altura e em diâmetro das mudas de H. impetiginosa, porém, influenciaram na produção de massa seca. Dessa forma, recomenda-se, para a produção de mudas de H. impetiginosa, a preparação do substrato sendo: solo com V60% de saturação por bases + 150 kg ha-1 de P2O5. Palavras-chave: Ipê rosa, calagem, fosfatagem, nutrição de plantas, viveiro. Abstract The pink ipe (Handroanthus impetiginosa) is a tree species native to Brazil that is used in forest ornamentation and restoration. To ensure that quality seedlings are used for any purpose, for which this species is used, it is necessary to know more about nutritional requirements. Therefore, an experiment was developed to evaluate base saturation and different phosphorus (P) levels in the pink ipe seedlings production. The experiment was carried out in a completely randomized design with nine treatments and five replications: T0 (100% commercial substrate); T1 (V50% of base saturation); T2 (V60% of base saturation); T3 (V50% of base saturation + 50 kg ha-1 of P2O5) ; T4 (V50% of base saturation + 100 kg ha-1 of P2O5); T5 (V50% of base saturation + 150 kg ha-1 of P2O5); T6 (V60% of base saturation + 50 kg ha-1 of P2O5); T7 (V60% of base saturation + 100 kg ha-1 of P2O5); T8 (V60% of base saturation + 150 kg ha-1 P2O5). Morphological characteristics of the plants were evaluated after 90 days. Base saturation and phosphate fertilization did not influence H. impetiginosa seedling height and diameter growth but influenced dry mass production. Thus, for the H. impetiginosa seedlings production, substrate preparation: soil with V60% of base saturation + 150 kg ha-1 of P2O5 is recommended. Keywords: Pink ipe, liming, phosphating, plant nutrition, nursery.

Extensive clonal propagation and resprouting drive the regeneration of a Brazilian dry forest

Woody plant resprouting has received considerable attention in the last two decades as human disturbances continue to encroach on terrestrial ecosystems globally. We examined the regeneration mechanisms of a Caatinga dry forest in the context of slash-and-burn agriculture and resprouting ability of the local flora. We excavated two old fields (from 32) experiencing early forest regeneration dominated by the tree Pityrocarpa moniliformis (Fabaceae) to map clonal propagation and, in parallel, submitted 260 seedlings from 13 woody plant species to experimental clipping. What seemed to be ‘seedlings’ popping up around P. moniliformis stumps and remaining adults actually were condensed sets of root suckers connected via complex networks of long, ramified shallow horizontal roots without taproots. We mapped respectively 39 and 783 connected root suckers, which summed 96 m and 910 m in root length. Regarding the seedlings, 33% resprouted across nine species with resprouting rates varying between 5–100%. Seedling height before clipping positively influenced resprouting vigour. Our preliminary results suggest that the Caatinga dry forest supports a relatively high proportion of resprouting species, some of them able to clonally propagate and playing an ecosystem-level role by responding to early forest regeneration and high abundance/biomass across both regenerating and old-growth forests.

PERTUMBUHAN BIBIT KEMIRI (Aleurites moluccana L.WILLD) DI LAHAN TERBUKA SETELAH DIBERI PERLAKUAN NAUNGAN DI PERSEMAIAN

The purpose of this study was to analyze the growth of candlenut seeds (Aleurites moluccana L. Willd) in open land after being given shade treatment in the nursery. The method used for observing the growth of candlenut seedlings is a Completely Randomized Design (CRD). The treatment in the nursery was shade levels consisting of 0%, 25%, 50% and 75%. Each treatment consisted of five samples and each treatment was repeated three times so that 4 × 5 × 3 = 60 seedlings were needed. Subsequent research was conducted on open land with 100% sunlight intensity. The parameters measured were height, diameter and number of leaves. Based on observations of candlenut seedlings in open land after being given shade treatment at the nursery for 12 weeks showed that the percentage of seedling life was 80%. The results of the variance analysis showed that the shade treatment significantly affected the growth of candlenut seedling height, but had no effect on the increase in diameter and the number of leaves.Keywords: Candlenut seedling growth; Open land; Shade

Morphological and Physiological Responses of Pinus massoniana Seedlings to Different Light Gradients

Light intensity is a critical factor regulating photosynthetic capacity in plants. However, the effects of varying light intensity on morphological and photoprotective mechanisms in Pinus massoniana seedlings have not been explored in depth, especially those in the first seedling growing season. We measured the growth, photosynthetic physiology, biochemistry, and chlorophyll fluorescence of P. massoniana seedlings at four light gradients: 100% relative irradiance (RI, full sunlight), 70% RI, 50% RI, and 20% RI. The seedling height at 70% RI was 9.27% higher than that at 100% RI. However, seedling height was inhibited under low light intensity; at 20% RI, all seedlings died. The decreasing light intensity inhibited ground diameter growth but increased the height-diameter ratio. The secondary needle emergence rate was 53.4% higher at 70% RI than at 100% RI but was only 2% at 50% RI. The chlorophyll and carotenoid contents increased significantly with decreasing light intensity. The increased Chl b and Car contents promoted the photoreceptor potential of the violet (400~420 nm), blue (440~480 nm), and yellow-orange (597~655 nm) regions in leaves. Among the chlorophyll fluorescence parameters, Fv/Fm, Fv′/Fm′, Y(II), qp, and ETR all reached maximum values at 70% RI but were significantly lower at 50% RI than at 100% RI. However, decreasing the light intensity caused a reduction in NPQ. The 70% RI level increased POD and SOD activity and the contents of osmotic regulation substances and slowed MDA accumulation. Seedlings at 70% RI had a higher growth rate, higher photosynthetic activity and potential, and significantly greater stress resistance than the other seedlings. Therefore, appropriate shading measures were beneficial to the cultivation of vigorous seedlings. Furthermore, spectral reflectance indexes were found to be a suitable tool for monitoring the photosynthetic physiological characteristics, stress resistance characteristics, and growth status of P. massoniana seedlings in real time.

Growth performance of Khaya senegalensis seedlings influenced by provenances and latitudinal gradients in the nursery

Seedling growth performance is germane and pertinent in plant variables when analyzing tree provenance trials as it indicates its adaptability of the seed to the environments/habitat. The study was undertaken to examine the comparative studies on seedling performance of Khaya senegalensis at nursery stage in Forestry Research Institute of Nigeria. Seeds from four sources in different States in Nigeria: Oyo, Borno, Jigawa and Kano States were collected and planted to observe their morphological attributes. Seedlings variables (Plant height, collar diameter and number of leaves) were observed and recorded fortnightly for sixteen (16) weeks after germination was completed. It was observed that seeds from Oyo state performed best while seeds from Kano state had the least performance. Provenances variation indicate genetic and environmental differences that can be utilized for afforestation programmes and thus, this study recommends the seeds from Oyo state for large scale afforestation since it performed best. Keywords: Khaya senegalensis, seed provenance, seedling height, collar diameter and number of leaves.