Rudy Erwiyono
ICCRI

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RELATIONSHIP BETWEEN DEPTH OF SOIL MOISTURE ASSESSMENT AND TURGIDITY OF COFFEE PLANT IN SELECTED AGROCLIMATES Erwiyono, Rudy; Wibawa, Aris
Journal of Tropical Soils Vol 13, No 2: May 2008
Publisher : UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5400/jts.2008.v13i2.111-122

Abstract

Observation on the relationship between the depth of soil moisture assessment and turgidity of coffee plant has been carried out at 3 different agroclimates by survey method, i.e. Andungsari experimental station (Andosol soil type, >1.000 m asl. high, and rainfall type of C), Sumberasin experimental station (yellowish-red Mediterranean soil type, 450-500 m asl. high, and rainfall type of C, and Kaliwining experimental station (low humic glei soil type, 45 m asl. high, and rainfall type of D) in order to assess the depth of soil moisture through soil profile influencing turgidity of coffee plants at three different agroclimates.    The method of assessment is by fitting the relationship between the depth of soil moisture assessment and turgidity of coffee plant and their determination coefficients through the period of dry season up to early rainy season.   Plant turgidity is evaluated from its relative water contents of the leaves sampled periodically at the same time as observation of soil moisture content.  Plant turgidity is affected by soil moisture condition up to a certain depth which looks to be typical of the agroclimates.  At Andungsari experimental station (high land) it is necessary to assess soil moisture through the soil profile up to 100 cm deep in order to evaluate water stress of the plants; inversely, at Kaliwining experimental station in order to evaluate water stress of the plants it is just justified from the soil moisture condition of the soil surface layers (0-25 cm).  Whereas at Sumberasin experimental station water stress of the plants could be predicted from soil moisture assessment of the surface layer depth or through the deeper layers of the soil profile either.  Andungsari-1 and Lini S-795 clones are more resistant to drought than Kartika-2 clone at Andisol soil type with C rainfall type and elevation > 1000 m asl.   BP-308 clone showed its response as relatively resistant to drought at yellowish red Mediterranean soil type with C rainfall type at elevation around 500 m asl.   Robusta coffee clone with no name at Kaliwining experimental station showed wilting sign, reduction of its turgidity, and falling leaves during the dry season, and positively responding to soil moisture increase.   An effort to maintain plant turgidity with increasing soil water stress could be done by managing atmospheric demand to be lower.  Practical implications of the findings might be discussed a bit more deeply in this paper. 
Soil Moisture and Turgidity of Selected Robusta Coffee Clones on Alluvial Plain with Seasonal Rainfall Pattern Erwiyono, Rudy
Pelita Perkebunan (Coffee and Cocoa Research Journal) Vol 21, No 2 (2005)
Publisher : Indonesian Coffee and Cocoa Research Institute

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Abstract

Observation on the seasonal variations of hydrological condition and turgidity of selected Robusta coffee clones has been carried out in Kaliwining Experimental Station, Indonesian Coffee and Cocoa Research Institute in Jember. The aim was to evaluate the effect of hydrological variation on the coffee plants and the degree of soil moisture effect on plant performance. Experimental site overlays on alluvial plain, + 45 m a.s.l., 8o 15’ South with D rainfall type. Observation was conducted by survey method at the experimental plots of organic fertilizer and nitogen treatments on selected Robusta coffee clones derived from rooted cuttings, i.e. BP 436, BP 42, BP 936 and BP 358. Observation was only conducted at the experimental blocks of organic matter trials of 20 l/tree/year at nitrogen (Urea) application of locally recommanded rate during the subsequent years of 1999 to 2001. Parameters observed included plant turgidity and soil moisture content of three different depths, i.e. 0—20, 20—40 and 40—60 cm and the weather. Observation was carried out in five replicates designed as blocks of barn manure treatment and N-fertilizer of recommended rate as basal fertilizer. The results showed that meteorological condition and soil moisture of experimental site through the years have seasonal patterns following the seasonal pattern of rainfall. Compared to other meteorological characteristics, relative humidity dominantly determined evaporation and plant turgidity. Plant turgi-dity was not only determined by soil moisture condition, but also atmospheric demand. When relative humidity (RH) was relatively high, plant turgidity was relatively stable although soil moisture of surface layers was very low, and the reversal when soil moisture content was high plant turgidity was controlled by atmospheric demand (relative humidity). With a 3—4 dry month period, relative turgidity of the coffee plants was relatively stable above 82%, except when soil moisture of 60 cm surface layer was below 25% (w/w) and or atmospheric demand was relatively high (RH 85%). Soil moisture contents of deeper soil layers seemed to have greater impact on the plant turgidity and the deeper the soil layers the narrower the seasonal variation of their soil moisture contents. Selected different clones originated from rooted cuttings showed different response to water stress and could be put in order from the most sensitive to water stress as follows BP 436, BP 42, BP 936 and BP 358. Barn manure application could significantly increase soil moisture content but its influence could not significantly increase plant turgidity.Key words : Seasonal variation, atmospheric condition, soil moisture, plant turgidity, Robusta coffee clones.
Effectiveness of Foliar Application of Potassium on Flowering and Fruiting of Cocoa Erwiyono, Rudy; Sucahyo, Achmad; ., Suyono; Winarso, Sugeng
Pelita Perkebunan (Coffee and Cocoa Research Journal) Vol 22, No 1 (2006)
Publisher : Indonesian Coffee and Cocoa Research Institute

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Abstract

An experiment of foliar application of potassium on cocoa has been carried out in Kaliwining Experimental Station, Indonesian Coffee and Cocoa Research Institute in Jember to study its effectiveness on the flowering and fruiting of cocoa. The experiment was arranged according to factorial design of 2 factors with environmental design of randomized complete blocks. The first factor was soil application of potassium fertilization in two levels, i.e. without fertilizer and with K-fertilizer as KCl. The second factor was application of potassium from two sources, i.e. KCl and KNO 3 , with 3 levels, i.e. without fertilizer (sprayed with water only), K-fertilizer as KCl and K-fertilizer as KNO 3. The experiment was done in 4 replicates. Parameters observed included newly formed flowers, new young fruits and the fresh-developing fruits. The results showed that foliar application of fertilizer was more effective than soil application and plant response was better in increasing new flower formation. On the other hand, the effect of soil application of fertilizer was slow. Foliar application of potassium followed by soil application of potassium fertilizer was more effective in the form of KNO 3 rather than in the form of KCl in increasing new flower formation. The dosage of foliar application of potassium could not significantly increase new young fruit formation. On the other hand, the dosage of soil application of potassium could increase new young fruit formation significantly. Key words: foliar application, kalium, flower, young fruit, cocoa.