Soil organic carbon and iron oxides affects soil aggregate stability under straw returning and potassium fertilizer in a rice--rape cropping system

Soil organic carbon (SOC) and iron (Fe) oxides are known to affect the formation and stability of soil aggregates. However, the effects of SOC and Fe oxides on soil aggregates stability under straw returning and potassium (K) fertilizer application in paddy–upland rotation systems are less well-studied. This study primarily investigated soil aggregates dynamics and their stability indices (mean weight diameter, MWD; geometric mean diameter, GMD), and soil binders (SOC and iron oxides) after rice and rape harvests under four treatments: F1，mineral nitrogen (N) and phosphorus (P) fertilizer; F2, mineral NPK fertilizer; F3, mineral NP fertilizer with straw returning; F4, mineral NPK fertilizer with straw returning in rice–rape cropping system. Straw returning treatments (F3 and F4) significantly (P <0.05) increased MWD and GMD, but the effect of K is not obvious. The soil aggregates stability was higher after the rape harvest than rice harvest, but SOC content was the opposite. Straw input can increase the contents of SOC, alkane-C and aromatic-C concentrations, especially in >0.25 mm aggregates. Long-term straw incorporation significantly increased the amorphous (Feo) and complex iron oxides (Fep) concentrations. SOC and Fep in bulk soil and >5 mm aggregates were significantly related with MWD, and significant relationship was observed between MWD and Feo in <5 mm fractions. Thus, the high levels of SOC, alkane-C, Feo and Fep in soil after straw returning were responsible for the aggregate stability, but the effect of potassium application is not obvious in a rice–rape cropping system.

Growth Enhancement, Uptake of N, P, K Nutrients and Production of Maize in an Entisol of Kalidawir, Tulungagung due to Application of Cow Manure Fertilizer and NPK Fertilizer

Entisols are newly formed soil types and are commonly found in Indonesia, with a distribution of ±3 million ha distribution. Entisol Kalidawir has a slightly acidic pH value of 5.8 and contains very low total-nitrogen (N) and available-phosphorus (P) nutrients, calcium (Ca), sodium (Na) and magnesium (Mg) in the exchangeable base are also low and clay loam texture. Low soil nutrients and organic matter can have an impact on plant growth and production Maize is one of the most widely cultivated food crops in Indonesia. The purpose of this study was to analyze various doses of the combination of cow manure and NPK fertilizer on N, P and potassium (K) uptake, growth and production of maize. The results showed that the application of 20 t ha-1 of cow manure and 400 kg ha-1 of NPK fertilizer at observations 27 and 54 days after planting increased growth in height and number of leaves of corn plants and increased nutrient uptake of N, P, and K, respectively. Also reached 1, 0.14, and 0.82 g plant-1 and 5.52, 0.83, and 5.11 g plant-1. In addition, it produces the highest corn production of 10.53 t ha-1.

Improving Ionic Exchange Process of Potassium in Poor Soils by Bentonite

The current study was carried out to improve ionic exchange for potassium in sandy and gypsiferous soils to obtain an increase in absorption of potassium ions in NPK fertilizers, the improving process includes two stages; The first is adding NPK fertilizer with concentrations (0.020%, 0.040%, and 0.070%) by weight for two samples, the exchange potassium concentration was measured and notice the increasing from 124 ppm to 140 ppm in sandy soil and from156 ppm to 180 ppm in gypsiferous soil when using the highest concentration (0.070%), the second stage included adding grinded bentonite ore (10%, 20%,30%) by weight to the two samples after treated with NPK fertilizer in same concentrations above, potassium exchange increased to 340 ppm in sandy soil and to 450 ppm in gypsiferous soil by using NPK fertilizer and bentonite ore concentrate (0.070% & 30%) respectively.

Aplikasi pupuk hayati ameliorant, dan pupuk NPK terhadap N total, P tersedia serta pertumbuhan dan hasil jagung pada inceptisols

Inceptisols umumnya memiliki tingkat kesuburan tanah rendah sampai sedang. Upaya peningkatan ketersediaan hara tanah Inceptisol dengan pupuk anorganik NPK perlu diimbangi dengan aplikasi pupuk hayati dan amelioran organik. Percobaan ini bertujuan untuk mengurangi dosis pupuk NPK dengan menggunakan pupuk hayati dan amelioran organik serta meningkatkan hasil tanaman jagung. Percobaan dilakukan di Pasir Banteng, Kabupaten Sumedang. Penelitian menggunakan RAK faktorial. Pupuk hayati dengan amelioran organik sebagai faktor pertama sebanyak empat taraf: tanpa pupuk hayati dan amelioran (kontrol), diberi pupuk hayati, amelioran organik, dan gabungan keduanya. Faktor kedua yaitu dosis pupuk NPK empat taraf: 100%, 80%, 60%, 40% NPK dosis anjuran. Dilakukan tiga kali ulangan. Hasil penelitian menunjukkan terdapat interaksi antara pupuk hayati, amelioran organik, dengan pupuk NPK terhadap tinggi tanaman, N-total tanah, bobot tongkol berkelobot dan tanpa kelobot. Pemberian pupuk hayati dan amelioran disertai pupuk NPK 100% dan yang tanpa diberi amelioran menghasilkan bobot tongkol tanpa kelobot sebesar 1.089 g dan 1.064 g per tanaman. Pemberian pupuk hayati dengan amelioran dan pemberian pupuk NPK 100% menghasilkan bobot pipilan per tanaman 526,08 g dan 539,08 g. Aplikasi pupuk hayati dan amelioran organik belum mampu mengurangi dosis penggunaan pupuk NPK pada Inceptisols asal Pasir Banteng. Inceptisols generally have low to moderate soil fertility. The effort to increase the nutrients availability in Inceptisol through the application of NPK fertilizers need to be balanced with biofertilizers and organic ameliorants. This experiment aimed to reduce the dose of NPK fertilizer by using biofertilizers and organic ameliorants and to increase maizeyields. The experiment was conducted in Pasir Banteng, Sumedang Regency. The factorial RBD was used. The biofertilizer with organic ameliorant as the first factor: no biofertilizer and no ameliorant (control), biofertilizer, organic ameliorant, and combination of both. The second factor was dose of NPK fertilizer: 100%, 80%, 60%, 40% of recommended NPK dose. It was repeated three times. The results showed that there was interaction between biofertilizer, organic ameliorants, with NPK fertilizers on plant height, N-total soil, weight of cobs with and without husk. The application of biofertilizer and ameliorant with 100% NPK fertilizer and without ameliorant were 1,089 g and 1,064 g of cobs without husks, respectively. The application of biofertilizer with ameliorant and 100% NPK fertilizer had a grain weight of 526.08 g and 539.08 g, respectively. The application of biofertilizers and organic ameliorants has not been able to reduce the dose of NPK fertilizer on Inceptisols from Pasir Banteng.

Seed Breaking Dormancy Technique and Growth of Screw Tree (Helicteres isora Linn.) seedlings

Screw tree is a shrub from family Malvaceae that has many benefits in pharmacy. Screw tree seed has very hard seed coat, so the seed must be treated before germination. The aim of this research was to assess the characteristic of fruit and seeds, effect of seed breaking dormancy, and effect of NPK fertilizer dosage on the growth of screw tree (Helicteres isora) seedlings. The results indicated that screw tree fruits belong to dry fruits with capsule form and has 5 follicles that has different direction. Screw tree seed is orthodox type that has 9 ̶ 36 seeds in one follicle with triangle and square shape. Germination technique in laboratory with soaking the seeds in hot water 100oC until the water cool for 48 hours treatment produced the best germination amounting to 65.0%. Germination technique in green house with soaking the seeds in hot water 100oC until the water cool for 24 hours treatment was the best germination amounting to 77.0%. Seedlings fertilized with 1 g NPK doses increased screw tree growth in diameter parameter of 6.35 mm and shoot-root ratio parameter of 3.9 compared to control.

The Growth of Lygodium circinnatum (Burn.F.) Swartz) Plants with Fertilization and Different Types of Vines Poles in The Research Forest Area of Rarung, Central Lombok

Ketak (Lygodium circinnatum (Burm.F) Sw.) is one of the main species of non-timber forest products (NTFPs) in West Nusa Tenggara. Ketak produce tendrils that was used as a raw material for the woven handicraft industry. The sustainability of the handicraft business has constraints in decreasing the supply of raw materials because the potential is very reduced in nature so that it is necessary to make efforts to cultivate L. circinnatum plants. The aim of the study was to determine the success of planting L. circinnatum with fertilization and different types of vines. The research used a randomized block design which was arranged factorially with a combination of different types of fertilizers (goat manure, cow manure, NPK fertilizer) and vine trees (Gliricidia sepium, Erythrina variegata, bamboo). For six months, the application of fertilizers and different types of climbing stems significantly affected the increase in tendril length and number of leaves and there was an interaction between the two treatments tested; while the increase in the number of tendrils and life percentage occurred the effect of a single treatment. Goat fertilizer and climbing species G. sepium were the best treatments for the increase in tendril length (73.4 cm) and number of leaves (88 sheet). The best NPK fertilizer treatment for the growth of the number of tendrils (3 tendrils), climbing species G. sepium and goat manure produced the highest percentage of life (80.42% and 85.56%)

Seed Breaking Dormancy Technique and Growth of Screw Tree (Helicteres isora Linn.) Seedlings

Screw tree is a shrub from family Malvaceae that has many benefits in pharmacy. Screw tree seed has very hard seed coat, so the seed must be treated before germination. The aim of this research was to assess the characteristic of fruit and seeds, effect of seed breaking dormancy, and effect of NPK fertilizer dosage on the growth of screw tree (Helicteres isora) seedlings. The results indicated that screw tree fruits belong to dry fruits with capsule form and has 5 follicles that has different direction. Screw tree seed is orthodox type that has 9 ̶ 36 seeds in one follicle with triangle and square shape. Germination technique in laboratory with soaking the seeds in hot water 100oC until the water cool for 48 hours treatment produced the best germination amounting to 65.0%. Germination technique in green house with soaking the seeds in hot water 100oC until the water cool for 24 hours treatment was the best germination amounting to 77.0%. Seedlings fertilized with 1 g NPK doses increased screw tree growth in diameter parameter of 6.35 mm and shoot-root ratio parameter of 3.9 compared to control.

PENGUJIAN BERBAGAI FORMULASI PUPUK TERHADAP PERTUMBUHAN DAN HASIL TANAMAN MELON (Cucumis melo L) PADA LAHAN KERING MASAM

Melon (Cucumis melo L.) contains various important vitamins and minerals, while melon consumption in Indonesia is still far below the standard. The increase in melon production every year has not met the needs of melons. Intensification of acid dry land is one of the efforts to increase melon production, because of the vast potential of the land, but it is necessary to improve the soil properties. The purpose of this study was to test the formulations on the growth and yield of melon plants on acid dry land. The study was conducted in a greenhouse using a non-factorial Randomized Block Design (RBD), with 8 treatments, namely: (A) without Lime + Phonska NPK Fertilizer (100%); (B) without Lime + Phonska NPK Fertilizer + Cow Manure (50%:100%); (C) without Lime + Phonska Npk Fertilizer + Petrobio Fertilizer (50%:100%); (D) without Lime + Phonska NPK Fertilizer + Cattle Fertilizer + Petrobio Fertilizer (50%:50%:50%); (E) with Lime + Phonska NPK Fertilizer (100%); (F) with Lime + Phonska Npk Fertilizer + Cow Manure (50%:100%); (G) with Lime + Phonska Npk Fertilizer + Petrobio Fertilizer (50%:100%); (H) with Lime + Phonska Npk Fertilizer + Cow Manure + Petrobio Fertilizer (50%:50%:50%) with 4 replications. Data analysis used Duncan's Multiple Range Test. The results showed that the fertilizer formulation with additional lime had a significant effect on fruit weight, fruit diameter, and fruit harvest age. Fertilization formulation without the need for high doses of organic fertilizer to achieve optimal yields.

Watermelon Production in Dry Land with Liquid Biofertilizer and Different Compound NPK

An area of 12.90 million ha of dry land has not been used optimally for agriculture, opportunity available to plant watermelons with proper cultivation techniques, including the use of biological and inorganic fertilizers. Biofertilizers can help provide NPK nutrients for watermelon plants. The purpose of this study was to determine the appropriate dosage of biological fertilizers and compound NPK for increasing watermelon yields. The research was conducted at AKN Sakojo No.21 Kel. Kedondong Raya Kec. Banyuasin III Pangkalan Banyuasin City Hall, South Sumatra from July to October 2020. This study used a factorial randomized block design (RAK). Factorial 1 is the dose of liquid biological fertilizer, namely: 10 mL/L, 20 mL/L, and 30 mL/L. Factorial II is Compound NPK, namely: 600 kg/ha, 900 kg/ha, and 1200 kg/ha. The highest production of 22.32 kg/plot (38 tons/ha) was achieved at a dose of 30 mL/L of liquid biological fertilizer and 1200 kg/ha of compound NPK fertilizer.