Pengaruh pengapuran dan pemupukkan P, K terhadap produktivitas dan kualitas buah papaya CV. Merah Muda di lahan rawa

Pepaya Merah Delima berpotensi untuk dibudidayakan di lahan rawa lebak. Permasalahan lahan rawa lebak yaitu pH rendah dan ketersediaan hara dalam tanah rendah sehingga perlu diberikan pengapuran dan pemupukan tambahan. Penelitian ini bertujuan untuk mendapatkan dosis kapur, pupuk P dan K terbaik untuk meningkatkan produktivitas dan kualitas pepaya Merah Delima. Penelitian dilakukan di lahan rawa lebak TTP Siak, Kecamatan Sai Mandau (BPTP Riau) dari bulan Januari 2018 sampai Desember 2019. Penelitian menggunakan Rancangan Petak Terbagi dengan petak utama yaitu dua taraf dosis kapur (6 dan 9 t ha-1) dan anak petak kombinasi dari tiga taraf dosis pupuk P2O5 (100, 200, 300 g tan-1) dan tiga taraf dosis pupuk K2O (150, 300, 450 g tan-1), setiap perlakuan terdapat tiga ulangan. Hasil penelitian menunjukkan pemberian kapur dosis 6 t ha-1 dan kombinasi P dan K dosis 300 g tan-1+ 300 g tan-1 berturut-turut, dapat meningkatkan produksi pepaya Merah Delima sampai 51% dengan rata-rata produksi 98,00 kg tan-1, jumlah buah rata-rata 95,45 tan-1, bobot buah 1.031,30 g buah-1, PTT 11,81 oBrix, dan kekerasan buah 55,08 kg cm-2. Pemberian kapur dan tambahan pupuk P dan K efektif untuk memperbaiki sifat lahan rawa lebak sehingga dapat meningkatkan hasil tanaman pepaya Merah Delima. Papaya CV. Merah Delima is potential to be cultivated on tidal swampland. The problems of tidal swampland are low degree of pH and low nutrient availability in the soil, thus it needs additional liming and fertilization. This study aimed to obtain the best dose of lime, also phosphorus and potassium fertilizers to increase the productivity and quality of papaya cv. Merah Delima. The study was conducted at TTP Siak, Sai Mandau district (BPTP Riau) from January 2018 to December 2019. The study used a Split Plot Design with the main plot was two doses of lime (6 and 9 t ha-1) and the subplot was combination of three doses of P2O5 fertilizer (100, 200, 300 g plant-1) and three levels of K2O fertilizer (150, 300, 450 g plant-1), with three replications. The results showed the application of lime at dose of 6 t ha-1 combined by P and K fertilizer of 300 g plant-1 + 300 g plant-1, respectively, could increase papaya production up to 51%, whereas average production 98.00 kg plant-1, average number of fruits 95.45 plant-1, fruit weight 1,031.30 g fruit-1, TSS 11.81 °Brix, and fruit hardness of 55.08 kg cm-2. Application of lime and additional fertilizer into the tidal swampland are effective to improve its characteristics and able to increase the papaya Merah Delima production.

Responses of Garlic Quality and Yields to Various Types and Rates of Potassium Fertilizer Applications

Potassium (K) is a critical plant nutrient that determines quality in a myriad of crops and increases production yields. However, excessive application of various types of K fertilizers can decrease both the food quality and yields, which translates as economic losses and food safety issues. The objectives of this study were to 1) elucidate the impacts of different application rates of various K fertilizers on garlic, with the aim to identify the optimal and most economical K fertilizer dosage and 2) compare the effects of applying two common K fertilizers (KCl and K2SO4) on garlic, to determine the optimal combination. From 2018 to 2020, we utilized two distinct K-fertilized fields to conduct our experiments. The results revealed optimal KCl fertilization increased the biomass and vegetation index in garlic, and promoted the transfer of nitrogen, phosphorus, and potassium nutrients from the stem and leaf to bulb, thereby increasing bulb production. The application of KCl fertilizer increased the number of cloves, the diameters of the cloves and bulbs, and reduced variations in bulb size. In addition, the application of KCl fertilizer improved the nutritional quality (Vitamin C, soluble sugar, soluble protein, and allicin) of the garlic and reduced the accumulation of nitrate. However, excessive KCl fertilizer cause decreased yields, appearance traits, and nutritional quality. Applying the same rate of K fertilizer in the form of K2SO4 in isolation increased the garlic yield by only 0.1% to 22.5% when compared with KCl fertilizer. However, the results were not always significant. In this study, the highest yields, appearance traits, and nutritional quality were achieved with the ratio of K2SO4: KCl = 3:1. Consequently, to ensure the highest economic value (considering the market prices of K fertilizer, garlic sprouts, and bulbs), the authors recommend a K fertilizer rate of 252.5 kg·ha−1 K2O, with K2SO4 accounting for 61.6% for garlic production in field.

A Facile Synthesis and Characterization of new Nitrogen, Phosphorus, Potassium (N-P-K) Fertilizer Fortified with Tri-micronutrient Matrix and its application for Optimal Plant Augmentation

At present in agricultural techniques engaged the optimal nutrient supply is very imperative factor for elevated crop yield and all essential plant macro and micronutrients. Micronutrients play vital role in photosynthesis. For balanced crop nutrition micronutrient support is essential. Micronutrient fertilizer required in small quantities by plants and occupy vital role in physiology of plant kingdom. Proven fact is decisive plant functions are over involved if enough micronutrients are engaged. In this paper the author developed a new N-P-K fertilizer fortified with tri -micronutrient matrix and its application for optimal Plant growth. The author developed and analyzed hundred percent water soluble active fertilizer(15-15-15) with three important micronutrients (-3.4 0.5%Zn, 0.5%Fe, 0.5% Mg). Pot experiments were conducted with and without proposed fertilizer on Solanum lycopersicum(tomato) seeds. The proposed enhanced efficiency fertilizer with tri micronutrient matrix showed better plant growth as compared to normal untreated fertilizer in low nutrient soil field.

Nutrient Use Efficiency Indices in Maize Hybrid as A Function of Various Rates of NPK in Mid Hills of Nepal

Field experiments were conducted to evaluate yield and nutrient use efficiency in maize in response to various rates of nitrogen (N), phosphorus (P) and potassium (K) in silty clay loam soil of Khumaltar, Nepal during 2019 and 2020. Three factorial randomized complete block designs with 27 treatment combinations were used in experiments, which were repeated three times. Three factors were N levels (150, 180, 210 N kg ha-1), P levels (40, 60, 80 P2O5 kg ha-1), and K levels (40, 60, 80 K2O kg ha-1). The results recommend to revise fertilizer dose since N210 kg ha-1 and K2O 80 kg/ha were optimum for increased maize production with grain yields of 10.95 t ha-1 and 10.54 t ha-1, respectively. Partial factor productivity, partial nutrient budget, internal efficiency, physiological efficiency, recovery efficiency, and agronomic efficiency of NPK for hybrid maize were mostly influenced by nutrient levels. Application of higher rate of P and K fertilizer improved maize N efficiencies, and case was valid for P and K efficiencies. Maize was more responsive to N and K fertilizer and lower rate of P application limited efficient use of applied N and K. To increase overall NUE, we recommend to revise dose of fertilizer for hybrid maize under mid hill condition of Nepal.

Stem Cutting Growth of Red Dragon Fruit (Hylocereus costaricensis) due to Aplication of Cow Manure and KCl in Andosol

This study aims to obtain the optimum dose of manure for red dragon fruit plant growth on Andosol, optimum K fertilizer dose for red dragon fruit plant growth on Andosol, and the interaction of manure and K fertilizer for red dragon fruit plant growth on Andosol. This research was conducted from August 2018 to November 2018 at the Horticulture Seed Center, Kepahiang Regency, Bengkulu Province. This study used a completely randomized design (CRD) consisting of two factors with three replications. The first factor is cow manure, which is 0 g/polybag, 20 g/polybag, 40 g/ polybag, and 60 g/polybag. The second factor is K fertilizer, which is 0 g/polybag, 1.38 g/polybag, 2.76 g/polybag, and 5.52 g/polybag. The results showed that the application of cow manure with a dose of 60 g/polybag resulted in the best shoot growth time and shoot fresh weight

Effects of Long-Term Straw Management and Potassium Fertilization on Crop Yield, Soil Properties and Microbial Community in a Rice–Oilseed Rape Rotation

The present study aims to assess the influences of long-term crop straw returning and recommended potassium fertilization on the dynamic change in rice and oilseed rape yield, soil properties, bacterial and fungal alpha diversity, and community composition in a rice–oilseed rape system. A long-term (2011–2020) field experiment was carried out in a selected paddy soil farmland in Jianghan Plain, central China. There were four treatments with three replications: NP, NPK, NPS, and NPKS, where nitrogen (N), phosphate (P), potassium (K), and (S) denote N fertilizer, P fertilizer, K fertilizer, and crop straw, respectively. Results showed that long-term K fertilization and crop straw returning could increase the crop yield at varying degrees for ten years. Compared with the NP treatment, the long-term crop straw incorporation with K fertilizer (NPKS treatment) was found to have the best effect, and the yield rates increased by 23.0% and 20.5% for rice and oilseed rape, respectively. The application of NPK fertilizer for ten years decreased the bacterial and fungal alpha diversity and the relative abundance of dominant bacterial and fungal taxa, whereas continuous straw incorporation had a contradictory effect. NPKS treatment significantly increased the relative abundance of some copiotrophic bacteria (Firmicutes, Gemmatimonadetes, and Proteobacteria) and fungi (Ascomycota). Available K, soil organic matter, dissolved organic carbon, and easily oxidized organic carbon were closely related to alterations in the composition of the dominant bacterial community; easily oxidized organic carbon, dissolved organic carbon, and slowly available K were significantly correlated with the fungal community. We conclude that long-term crop straw returning to the field accompanied with K fertilizer should be employed in rice-growing regions to achieve not only higher crop yield but also the increase in soil active organic carbon and available K content and the improvement of the biological quality of farmland.

The effects of straw-returning and inorganic K fertilizer on the carbon–nitrogen balance and reproductive growth of cotton

Background Many studies have indicated that straw-returning could meet part or even all of the potassium (K) demand for crop growth in the field, but few have compared the effects of crop straw as K source and inorganic K fertilizer on carbon–nitrogen (C–N) balance of cotton and the reproductive growth. To address this, field experiments were conducted using the cotton cultivar, Siza 3, under there treatments (CK as control group one, no crop straw and inorganic K fertilizer were applied; K150 as control group two, 150 kg·ha−1 of K2O was applied; and W9000, 9 000 kg·ha−1 wheat straw, which could provide K2O about 150 kg·ha−1, was incorporated into soil). Results Although the final reproductive organ biomass did not differ between W9000 and K150, W9000 had a higher ratio of reproductive organ biomass to total biomass (RRT), suggesting that straw-returning was more conducive to the allocation of biomass to reproductive organs. The theoretical maximum biomass of reproductive organ was higher, but the average and maximum accumulation rates of reproductive organ biomass were 2.8%∼8.3% and 2.5%∼8.2% lower under W9000 than K150. Also, the duration of rapid-accumulation period for reproductive organ biomass (T) was 2.0∼2.8 d longer under W9000 than K150, which was a reason for the higher RRT under W9000. Straw-returning altered the dynamics of leaf K with the growth period, so that W9000 had a more drastic effect on leaf C metabolism than K150. Consequently, lower soluble sugar/free amino acid and C/N ratios were measured under W9000 than K150 at boll-setting (BSS) and boll-opening (BOS) stages. Higher leaf net photosynthetic rate, sucrose phosphate synthase and sucrose synthase activities, and lower acid invertase activity were observed under W9000 than K150 at BSS and BOS and these were more conducive to sucrose accumulation. However, less sucrose was measured under W9000 than K150 at these stages. This should be because straw-returning promoted the assimilate transport capacity when compared with inorganic K fertilizer application, which also explained the higher RRT under W9000 than K150. The lower acid invertase activity under W9000 inhibited the conversion of sucrose to other sugars, hence lower contents of soluble sugar and starch were measured under W9000 than K150. Conclusion Under low K condition, crop straw as K source can increase the assimilate transport from source to sink, leading to lower C/N ratio in leaf and higher allocation of biomass to reproductive organs than inorganic K fertilizer.

Essential Role of Potassium in Apple and Its Implications for Management of Orchard Fertilization

K (K) is of paramount importance for apple (Malus × domestica Borkh.), not only for tree growth and development but also for the size and quality of fruit yield. The apple plant’s demand for K varies, along with the progression of phenological phases, during the growing season. The K demand peaks during ripening of fruits featuring relatively high concentration of K comparable to that of the leaves. The mainstream method of apple tree K fertilization is through application of the fertilizer to the soils to improve K uptake by the roots. The bioavailability of K depends on assorted various factors, including pH, interaction with other nutrients in soil solution, temperature, and humidity. An important role in making the K from soil available for uptake by plants is played by plant growth-promoting microorganisms (PGPM), and the specific role of the PGPM is discussed. Advantages of fertigation (the combination of irrigation and fertilization) as an approach include allowing to balance application rate of K fertilizer against its variable demand by plants during the growing season. Excess K in the soil leads to competitive inhibition of calcium uptake by plants. The K-dependent deficiency of Ca leads to its predominant channeling to the leaves and hence to its decline in fruits. Consequently, the apple fruits affected by the K/Ca imbalance frequently develop physiological disorders in storage. This emphasizes the importance of the balanced K application, especially during the last months of the growing season, depending on the crop load and the actual K demand. The potential use of modern approaches to automated crop load estimation through machine vision for adjustment of K fertilization is underlined.

Long-term straw returning improve soil K balance and potassium supplying ability under rice and wheat cultivation

The aims of the present study were to provide scientific bases for rational use of crop straw to substitute chemical potassium (K) input. The effects of potassium fertilization and straw incorporation on soil K balance and K supplying in a long-term (14 years) field experiment. Five treatments were examined: (1) no fertilization (CK); (2) mineral fertilizing (NPK); (3) straw 6000 kg h m−2 (S); (4) NPK with straw 3000 kg h m−2 (NPK1/2S); and (5) NPK with straw 6000 kg h m−2 (NPKS). K composition, K balance and quantity-intensity (Q/I) relationship were studied. Under no fertilization or low straw returned conditions, soil K was unbalanced and deficienct seriously. Straw return at 6000 kg h m−2 per season with fertilization improved the soil potassium supply and K balance. Long-term K surplus (4 or 5 years), compared with NPK, the NPKS significantly increased non-special K adsorption (Knsa) and non-exchangeable K (Kne) by 5.7–11.2 mg kg−1 and 65.7–128.1 mg kg−1, respectively. Q/I relationship showed cropping without straw K or without fertilizer K resulted in lower quantity (nonspecifically and specifically held K i.e. – ∆K0 and Kx) and intensity (equilibrium activity ratio i.e. CR0K) of K in tested soils. K-fertilization with straw maintain higher exchangeable K (EK0) and a higher difference between EK0 and minimum exchangeable K(EKmin), and would help to prevent depletion in non-exchangeable pool of soil K under intensive cropping. Additionally, The straw return mainly decreased potential buffering capacity for exchangeable pool (PBCKn), 43.92–48.22% of added K in soil might be converted to exchangeable pool while it was 25.67–29.19% be converted to non-exchangeable pool. The contribution of exchangeable K towards plant K uptake would be higher in the soil with straw than the soil without straw and the non-exchangeable K would be the long-term fixed K as a supplement to the potassium pool. K fertilizer with 6000 kg h m−2 straw return in each crop season increased soil available K and slowly available K. The findings underlined importance of the straw return and contribution for sustain K supplying ability of soils.

Potassium and Water-Deficient Conditions Influence the Growth, Yield and Quality of Ratoon Sugarcane (Saccharum officinarum L.) in a Semi-Arid Agroecosystem

Groundwater and soil potassium deficiencies are present in northern India. Sugarcane is a vital crop in the Indian Punjab; it is grown on approximately 91,000 hectares with an average yield of 80 tonnes ha−1 and a sugar recovery rate of 9.59%. The role of potassium (K) fertilizer under both sufficient and deficient irrigation in ratoon sugarcane crops is not well documented. We conducted a split-plot ratoon cane experiment during 2020–2021 at the Gurdaspur Regional Research Station of Punjab Agricultural University, India, on K-deficient soils. Main treatments were fully irrigated (I1) and water stressed (I0) conditions, with sub-treatments reflecting K fertilizer application rates of 0 (M1), 67 (M2), 133 (M3), and 200 (M4) kg K ha−1. The ratoon sugarcane performance was assessed in terms of growth, productivity, sugar quality and incidence of key insect pests. At harvest, trends in the growth and yield parameters in I1 were improved over the I0 treatment, with cane height (+12.2%), diameter (+3.3%), number of internodes (+5.4%), biomass yield (+7.6%) and cane yield (+5.9%) all higher, although little significant difference was observed between treatments. Ratoon cane yield under irrigation was 57.1 tonnes ha−1; in water-stressed conditions, it was 54.7 tonnes ha−1. In terms of sugarcane quality parameters, measured 12 months after harvesting the initial seed crop, values of Brix (+3.6%), pol (+3.9%), commercial cane sugar percentage (+4.0%) and extractable sugar percentage (+2.8%) were all higher in the irrigated treatments than the water-stressed plot. Irrigated treatments also had a significantly lower incidence of two key insect pests: top borer (Scirpophaga excerptalis) was reduced by 18.5% and stalk borer (Chilo auricilius) by 21.7%. The M3 and M4 treatments resulted in the highest cane yield and lowest incidence of insect pests compared to other K-fertilizer treatments. Economic return on K-fertilizer application increased with increasing fertilizer dosage. Under the potassium-deficient water-stressed conditions of the region of north India, a fertilizer application rate of 133 kg K ha−1 is recommended to improve ratoon sugarcane growth, yield, and quality parameters and economic returns for sugarcane farmers.