Calcium (Ca) in flesh fruits is important for quality formation and maintenance. Most studies on fruit Ca focus on one species. This study attempted to understand some universal relations to fruit Ca uptake across species. Calcium contents in fruit tissues were analyzed in different fruits, including three cultivars of litchi, two cultivars each of grape and citrus, and one cultivar each of loquat, apple, pear, Indian jujube, and longan. In situ Ca distribution was revealed with electron probe and xylem functionality visualized by dye tracing. Fruit Ca uptake rate and activity were calculated and correlated with fruit growth and pedicel anatomy. The results showed that fruit Ca uptake rate was the highest in pomes (loquat, apple, and pear), followed by Indian jujube drupe, arillate fruits (litchis and longan) and citrus, while grape berries were the lowest. Fruit Ca uptake rate showed a strong positive correlation to growth rate. However, Ca uptake activity, reflecting Ca uptake rate relative to growth, was the highest in arillate fruits and loquat and lowest in grape berries, and had a poor correlation with fruit growth rate. In all fruits, Ca concentration in the pedicel was higher than in the fruit, and they displayed a good positive correlation. In the pedicel, Ca was most abundant in the phloem. Dye tracing showed that xylem function loss occurred with maturation in all species/varieties. Apple had the poorest xylem functionality with the least development of secondary xylem, but its Ca uptake rate was among the highest. Vessel density, size and area in the pedicel showed no correlation with fruit Ca uptake rate. It is concluded that: (1) fruit growth may be a key determinant of Ca uptake; (2) the universal pattern of Ca being higher in the pedicel than in the fruit indicates existence of a pedicel-fruit “bottleneck” effect in Ca transport across species; (3) xylem functionality loss with fruit maturation is also a universal event; (4) in the pedicel, Ca is more distributed in the phloem; (5) vessel morphology in the pedicel is not rate-limiting for fruit Ca uptake; (6) phloem pathway might contribute to fruit Ca uptake.

Tujuan penelitian adalah untuk mengetahui pengaruh pemberian pupuk kandang ayam dan jarak tanam yang berbeda terhadap komponen produksi rumput gajah mini (Pennisetum purpureum cv. Mott). Percobaan dilaksanakan di desa Makroman, kecamatan Sambutan, kota Samarinda. Rancangan yang digunakan adalah Rancangan Acak Kelompok (RAK) dengan pola faktorial, dimana perlakuan dosis pupuk kandang ayam terdiri atas 4 perlakuan, yaitu 0 ton ha-1 (p0), 5 ton ha-1 (p1), 10 ton ha-1 (p2) dan 15 ton ha-1 (p3), sedangkan perlakuan jarak tanam terdiri atas 3 perlakuan, yaitu 50 x 100 cm (k1), 75 x 100 cm (k2), dan 100 x 100 cm (k3). Seluruh perlakuan diulang sebanyak 3 kali. Data dianalisis dengan analisis sidik ragam yang dilanjutkan dengan uji beda nyata terkecil pada taraf 5%. Variabel yang diamati meliputi tinggi tanaman, panjang daun, jumlah daun, jumlah anakan, berat  segar, berat kering, dan imbangan daun/batang.  Hasil penelitian menunjukkan bahwa dosis pupuk kandang ayam memberikan pengaruh yang nyata terhadap tinggi tanaman, panjang daun, jumlah daun, jumlah anakan, berat segar dan berat kering, sedangkan perlakuan jarak tanam berpengaruh nyata pada tinggi tanaman, panjang daun, berat kering, dan imbangan daun/batang. Tidak terjadi interaksi  antara perlakuan dosis pupuk kandang dan jarak tanam terhadap seluruh komponen produksi rumput gajah mini yang diukur.

Kalimantan Island is rich in genetic resources and species diversity of Durio spp. plant. The large number of Durio species that grow in Kalimantan illustrates that this area is the most important distribution center for durian relatives. The best-known edible durians are Durian (Durio zibethinus). However, Kalimantan also has various types of Durian that are not yet widely known and have superior potential. One of the unique and exotic plants is the red flesh Durian in East Kalimantan, Indonesia. The fruit of this plant is unique because it has red flesh. At present, there is no morphological identification of this East Kalimantan Durio graveolens plant. The study aimed to identify the morphological character of Batuah D. graveolens from East Kalimantan, Indonesia. This research was carried out by collecting data and information about the morphological characteristics of the plant and fruits. The results of the study successfully identified Batuah D. graveolens from East Kalimantan as a plant diverts from another Durio spp. plant known like D. zibethinus and D. kutejensis especially for red flesh character.

Kalimantan Island is rich in genetic resources and species diversity of Durio spp. Of the 27 durian species in the world, 18 species are found in Borneo. The large number of Durio species that grow in Kalimantan illustrates that this area is the most important distribution center for durian relatives. Two of the best-known edible durians in East Kalimantan are Durian (Duriozibethinus) and Lai (Durio kutejensis). However, as a plant with a cross-pollination mechanism, there are many results of natural crosses between the two. The study aimed to identify Durian x Lai plants in Loa Kulu, Kutai Kertanegara, East Kalimantan Province, Indonesia as the superior local fruit crops potentially agribusiness industry. This research was carried out by collecting data and information about the morphological characteristics of the plants and fruits from D. Zibenthinus x D. Kutejensis. The results of the study successfully identified 6 potentially superior plants that are believed to be the result of a cross between D. Zibenthinus x D. kutenjensis. The 6 potential superior plants were found to have different morphological characters. This is the initial identification and being a basis of the next research phase, which is to identify the morphology of trees, flowers, and fruit to obtain new cultivars crossing D.zibenthinus and D. Kutejensis which have superior potential as superior commodities from East Kalimantan.

Cemaran getah kuning pada buah manggis akan menurunkan kualitas buah. Cemaran getah kuning terjadi pada saat getah mencemari permukaan kulit buah atau aril akibat pecahnya saluran getah kuning. Pecahnya saluran getah kuning berkaitan dengan keberadaan kalsium dalam pericarp buah. Penelitian ini bertujuan untuk (1) mendapatkan dosis dan sumber kalsium  terbaik dan efisien dalam menurunkan cemaran getah kuning pada buah manggis, (2) mengetahui pengaruh lubang resapan biopori di dalam usaha mengatasi cemaran getah kuning pada buah manggis, dan (3) mengetahui kombinasi terbaik dari aplikasi kalsium dan lubang resapan biopori untuk meningkatkan serapan dan translokasi kalsium ke buah dan dapat menanggulangi cemaran getah kuning pada buah manggis. Hasil penelitian ini menunjukkan: (1) pemberian kalsium, baik bersumber dari dolomit maupun kalsit, mampu menurunkan cemaran getah kuning pada aril maupun kulit buah manggis, (2) berdasarkan efisiensi dan efektifitas maka dosis pupuk kalsium sebesar 1,6 kg kalsium kalsit/pohon/tahun menjadi dosis terbaik dalam mengatasi cemaran getah kuning, (3) teknologi lubang resapan biopori dapat meningkatkan pertumbuhan dan perkembangan akar muda yang selanjutnya dapat meningkatkan serapan kalsium dan menurunkan cemaran getah kuning setelah 2 tahun aplikasi, (4) kombinasi 1,6 kg kalsium kalsit/pohon/tahun dengan teknologi lubang resapan biopori (LRB) merupakan teknik yang efektif dan mampu meningkatkan persentase produksi buah manggis berkualitas bebas cemaran getah kuning.