Pengaruh Berbagai Campuran Media yang Diperkaya Mikoriza Terhadap Pertumbuhan Benih Petai (The Effect of Several Media Mixtures Enriched by Mycorrhiza for Stink Bean Seedlings Growth)

<p>Media tanam mempunyai peran penting dalam menghasilkan benih petai bermutu. Namun, informasi mengenai media tanam yang dapat memacu pertumbuhan benih dan menghambat serangan penyakit tular tanah pada tanaman petai belum banyak tersedia. Tujuan dari penelitian ini adalah untuk memperoleh satu komposisi media terbaik untuk pertumbuhan benih petai. Penelitian dilaksanakan pada bulan September 2017 – April 2018 di Kebun Percobaan Sumani Balai Penelitian Tanaman Buah Tropika Solok, Sumatra Barat. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok Lengkap (RAKL) dengan 10 perlakuan dan tiga ulangan, setiap unit perlakuan terdiri atas 30 tanaman. Perlakuan yang digunakan adalah 10 komposisi media yang terdiri atas kombinasi dua atau tiga bahan yang terdiri atas tanah, pupuk kandang, kompos, dan arang sekam serta penambahan agens hayati mikoriza. Hasil penelitian menunjukkan bahwa media terbaik untuk pertumbuhan benih petai sampai 6 bulan setelah transplanting adalah tanah: pupuk kandang = 1 : 1 (v/v) di mana menghasilkan bobot kering tanaman sebesar 24,47 g sementara media yang sama dengan penambahan mikoriza menghasilkan bobot kering tanaman lebih tinggi, yaitu sebesar 29,94 g, namun tidak berbeda secara signifikan dengan media tanpa penambahan mikoriza. Hasil penelitian ini dapat digunakan sebagai dasar pemilihan media untuk perbenihan petai.</p><p><strong>Keywords</strong></p><p>Campuran media; Mikoriza; Pertumbuhan; Petai</p><p><strong>Abstract</strong></p><p>Planting media used has an important role in producing quality stink bean seedling. However, information about planting media that can enhance seedling growth and inhibit infectious soilborne diseases on stink bean plants is not yet available. The purposes of this study were to obtain the best media compositions for the growth of stink bean seedlings. The research was conducted in September 2017 – April 2018 at Sumani Experimental Station of Balitbu Tropika, Solok, West Sumatra. The experimental design used was Randomized Complete Block Design (RCBD) with 10 treatments and three replications in which each treatment unit consisted of 30 plants. The treatments used were 10 media compositions consisting of a combination of two or three materials comprising soil, manure, compost, and rice husk charcoal and the addition of mycorrhizal biological agent. The results showed that the best medium for stink bean seedling growth up to 6 months after transplanting was soil: manure = 1 : 1 (v/v) which produced total plant dry weight 24.47 g whereas the same media with addition of mycorrhiza produced higher total dry weight 29.94 g, however this result did not show significantly different with treatment without mycorrhiza. This result can be used for media selection of stink bean seedlings.</p>

Laser Irradiation of Mung Bean (Vigna radiata L.) at Two Wavelengths for Enhanced Seedling Development

Two laser sources operating at wavelengths of 632.8 nm (He-Ne) and 488 nm (Ar+) are used in examining the effects of coherent, low-power, continuous wave exposure on the development of Vigna radiata L. Presowing laser irradiation of seeds leads to an improvement of mung bean seedling characteristics, with increased values of hypocotyl length (an increase of up to 22.5%), root length (an increase of up to 28.8%), and seedling mass (a maximum increase of 29.2%). Measured parameters between seedlings from laser-irradiated seeds and from control samples are statistically different at a level of significance equal to 0.05. For both laser wavelengths, an optimal exposure time of 2 minutes is determined for enhanced growth of mung bean seedlings.

Isolation and Characterization of Indole-3-Acetic Acid Producing Bacteria from Cow Urine

Cow urine contains urea as nitrogen source, therefore it can be expected to isolate the beneficial bacteria for plants, for example indole-3-acetic acid (IAA) or auxin producing bacteria. The objective of research was to obtain IAA producing bacteria from cow urine, to characterize bacterial isolate, and to measure its ability to stimulate the growth of green bean seedlings (Vigna radiata). The methods used in this study were collecting urine from cow cattle, obtaining IAA-pro-ducing bacteria from urine, measuring IAA using Salkowski method, and applying selected bacterial supernatants on green bean seedling plants. The number of IAA producing bacteria that was successfully purified was 18 isolates. There are five isolates, namely US 5, BS1, BS 2, BS 4 and BS 5 which have the ability to solubelize phosphate on Pikovskaya agar. The five isolates were also able to fix free nitro-gen on N Free media and did not show hypersensitivity on tobacco leaves. The results of the growth of isolates in blood agar showed positive for US 5 and BS 2 as beta hemolysin producers. Further-more, isolate BS 4 was chosen to produce exogenous IAA quantita-tively. Isolate BS 4 produced IAA 6.364 ppm at the 45 h incubation at stationary phase. The use of BS 4 supernatant on green bean seed-lings showed an effect on plant height and lateral root length better than control (without treatment) on 6 days after planting. Morpho-logical characteristic of isolate BS 4 was rod shape, Gram positive, endospore producing, aerobic, and had similarity with genus Bacillus

Anatomical and physiological traits of broad bean (Vicia faba L.) seedling affected by salicylic acid and salt stress

A laboratory experiment was carried out at the College of Agriculture University of Baghdad in 2017. The aim was to improve the anatomical and physiological traits of broad bean seedling under salt stress by soaking it in salicylic acid. The concentrations of salicylic acid were 0, 10, and 20 mg L-1 and the electrical conductivity levels were 0, 3, and 6 dS m-1. The complete randomized design was used with four replications. The increasing of salicylic acid concentration up to 10 mg L-1 led to increasing the stem cortex thickness, stem vascular bundles thickness, and root cortex thickness significantly by (34.9,36.7,and 55 µm) respectively, while the treatment of 20 mg L-1 led to decreasing these traits by (28.2, 27.8, and 48.1 µm), compared to control treatment (33.8, 35.9, and 53.8 µm), respectively, and the interaction of studied factors led to increasing those traits up to 10 mg L-1 and then decreased up to 20 mg L-1 of salicylic acid under each level of electrical conductivity. Therefore, it is recommended to soak the broad been seeds with 10 mg L-1 salicylic acid to improve the anatomical traits of seedlings and increase their tolerance to salt stress up to 6 dS m-1.

Sugarcane and Pine Biochar as Amendments for Greenhouse Growing Media for the Production of Bean (Phaseolus vulgaris L.) Seedlings

Louisiana sugarcane farmers in 2016 harvested 11.7 million Mg of millable sugarcane from 163,000 ha, producing 1.47 million Mg of raw sugar and an estimated 3.5 million Mg of bagasse. Even though Louisiana sugar mills use 80% to 90% of the bagasse for fuel production, another 350,000 to 700,000 Mg of bagasse accumulates each year. The conversion of the excess bagasse into biochar is one solution to reduce the excess supply. Research was conducted to determine the impact of sugarcane biochar as an amendment to soilless planting media for the production of green bean (Phaseolus vulgaris L.) seedlings. Sugarcane bagasse biochar (SBB) and pine biochar (PB) were each combined by volume with a commercial certified organic soilless growing media into 5 combinations (0%:100%, 25%:75%, 50%:50%, 75%:25%, and 100%:0%, biochars and growing media, respectively). Green bean variety ‘Bowie’ seeds were planted in each of the different planting mixtures. The particle size distribution for the two biochars are in stark contrast to each other with the PB particle median, mean, geometric mean, and mode much greater than those of the SBB. As amendments to the soilless greenhouse growing media, the biochars (SBB and PB) functioned very well, especially at the 25% and 75% levels. The 100% SBB performed as well as the 100% commercial soilless growing media and slightly better than the 100% PB when comparing seedling fresh and dry weights. The 100% PB is not recommended as a soilless growing media even with the supplemental fertilizer used in these experiments. These results indicate that the volume of a standard soilless greenhouse growing media can be successfully extended by adding 25% to 75% SBB and PB without reducing bean seedling growth. Future research is needed to evaluate these biochars for the production of additional plant species.

Meeting Initial Snap Bean Seedling Requirements with Starter Phosphorus or Bicarbonate to Solubilize Soil Phosphorus in High-phosphorus Soils

Starter phosphorus (P) is often recommended for warm-season vegetables sown in cool soil, even if soil P index levels are already high. The cost and environmental risk associated with excessive P fertilization justify re-examination of the practice. The objective of the study was to confirm that performance of early plantings of snap bean (Phaseolus vulgaris L.) is improved by starter P application and to test whether solubilizing soil P with potassium bicarbonate (KHCO3) can serve as an alternative in western New York soils. Addition of starter fertilizer at either recommended (15 kg·ha−1) or supraoptimal (35 kg·ha−1) P rates did not generally improve seedling tissue P concentration, early growth (biomass at flowering), or pod yield. Starter P application increased tissue P in only two of 11 experiments, and it never increased yield. Application of 6 kg·ha−1 KHCO3 to release soil-bound phosphate was not phytotoxic to snap beans. In the two experiments in which starter P increased tissue P, KHCO3 application had a smaller effect in one and no effect in the other. KHCO3 application did not increase yield in any of the six experiments where it was tested. A direct test of the contribution of P limitation to the poorer performance of early plantings showed that neither starter P nor KHCO3 application increased yield at early planting. Seasonal differences in crop performance could not be attributed to mineralization of soil phosphate after soil warmed. Water-extractable soil P was not lower in the spring than in summer, remaining constant at all 11 bean fields that were sampled from mid-April through mid-July. In these trials, P was likely not growth-limiting in the cool soils tested. Because starter P may not be necessary in vegetable soils testing high or very high for P, vegetables would also not likely benefit from bicarbonate application under high P conditions.