Vermicompost Compost Worm Casting Spinach Fertiliser is one of the important components in agricultural practices, mainly applied to increase plant's productivity and soil's quality. However, the use of chemical fertiliser is still favourable among most of the farmers due to its great contribution on improving crop yields. Currently, organic fertiliser is widely used to substitute chemical fertiliser as it can reduce the risk of build-ups of toxic chemical, making it as sustainable and environmental friendly option in agriculture farming system. There are various types of organic fertilisers, including vermicompost and compost. Worm casting is a type of organic fertiliser produced from a mixture of earthworm drop (or waste) and other organic materials. While compost is an organic fertiliser derived from the decomposition of plant or animal waste and/or a mixture of both wastes. Organic fertiliser can improve the chemical, physical and biological properties of the soil and can be used in various agricultural businesses such as vegetables, ornamental plants, fruits, and etc. This research aimed to compare the quality of vermicompost and commercial compost, as well as to evaluate their application on the growth of red spinach plant growth. The results indicated that vermicompost has superior quality compared with commercial compost. Further application of vermicompost has significantly enhanced the growth of red spinach, as indicated by the highest number of plant leaves and height.

The assimilate obtained during the grain filling phase is sourced from photosynthesis and Non Structural Carbohydrate (NSC) reserves produced during the vegetative phase in the vegetative organs. Assimilate from different sources plays different roles in the grain filling process. This study aims to investigate varietal difference on assimilate distribution, nitrogen response and yield performance. The experiment was carried out in the rice fields of Petapahan Village, Kampar Regency, Riau. The experimental design used was a split-plot in randomized complete block design (RCBD) with 2 factors and 3 groups. The first factor, as the main plot, was the condition of N. Specifically without N (NoN) (0 kg ha−1 urea) and treatment with normal N (NN) (250 kg ha−1 urea). The second factor, as a sub-plot, was rice variety, spesifically Hipa 18, IPB 3S, Ciherang, and Way Apo Buru. Hipa 18 was a variety having the largest reserves of NSC. A positive correlation was found between plant characters observed in this research, they are stem and leaf dry weight, total carbohydrates in stems (proximate analysis), photosynthetic rate, and leaf nitrogen content (Kjeldahl method). As well as other agonomic characters such as leaf area index and yield components. The highest dry weight of stems and leaves of Hipa 18 was at the heading phase, 22.6 g. While the highest carbohydrate content of the stems of the variety was 7.93 g in the same phase. This large NSC reserve supported the largest sinks as well at Hipa 18. However, the source capacity of the varieties used was found to be lower than the sink capacity. It was also known that nitrogen affected the condition of all plant characters observed in this study. Therefore optimal nitrogen fertilization is needed to get a maximum yield. HIGHLIGHTS Production of dry matter through photosynthesis and remobilization of assimilate from vegetative organs are the main sources of grain filling There was a greater amount of assimilate remobilization in Hipa 18 compared to IPB 3S, Ciherang, and Way Apo Buru The yield was positively correlated with plant height at harvest, stem and leaf dry weight, leaf N content, leaf area index, total stem carbohydrates, and photosynthesis GRAPHICAL ABSTRACT

Unsur nitrogen (N) memainkan peran penting pada tanaman padi termasuk dalam meningkatkan hasil tanaman. Terdapatnya perbedaan hasil gabah pada masing-masing varietas padi sangat erat kaitannya dengan karakter pengisian biji. Dengan demikian, respon karakter pengisian biji dan hasil dari varietas padi yang berbeda terhadap kondisi N di dalam tanah sangat relevan untuk dikaji. Tujuan penelitian ini adalah untuk mengkaji respon karakter pengisian biji dan hasil empat varietas padi terhadap pemberian pupuk urea. Penelitian ini dilaksanakan di lahan persawahan Desa Petapahan, Kampar, Riau pada bulan September sampai Desember 2020. Rancangan percobaan yang digunakan adalah rancangan petak terbagi dalam rancangan acak kelompok. Dosis pupuk urea (0 kg ha-1 dan 250 kg ha-1) merupakan faktor pertama sebagai petak utama, sedangkan varietas (Hipa 18, IPB 3S, Ciherang dan Way Apo Buru) merupakan faktor kedua sebagai anak petak. Berdasarkan hasil penelitian diketahui bahwa Hipa 18 merupakan varietas padi yang melakukan remobilisasi asimilat dalam jumlah yang paling banyak selama fase pengisian biji. Selain itu, Hipa 18 juga menggunakan N dalam persentase yang paling tinggi untuk pembentukan dan perkembangan malai dibandingkan varietas lainnya. Respon tertinggi untuk semua komponen hasil juga diperoleh dari Hipa 18 kecuali bobot 100 biji. Hasil penelitian ini dapat digunakan sebagai dasar dalam merakit varietas padi yang memiliki karakterisik hasil tinggi. Disamping itu, pemupukan yang presisi untuk masing-masing varietas padi dapat direkomendasikan. Kata kunci: bobot kering, fotosintesis, indeks luas daun, kandungan N daun, remobilisasi asimilat