REFERENCE SUFFICIENCY RANGES
FIELD CROPS

Sugarcane

G. J. Gascho

• Critical Values
  
  Critical values in the literature vary with plant part sampled, plant age, variety and with the time of the day sampled. For the top-visible dewlap leaf during the "Grand Growth" period, the following critical levels have been published (Evans 1956; Gascho and Elwali 1978).
  
  

  Macronutrients
  N	P	K	Ca	Mg	S
  1.80%	0.19%	0.90%	0.20%	0.12%

  
  

  Micronutrients
  Fe	Mn	Zn	Cu	B
  5 ppm	25 ppm	15 ppm	3 ppm	4 ppm

• Sampling Procedures

  Several systems have evolved in tissue sampling of sugarcane. Much is sampled just prior to the "Grand Growth" period. However, that period is often difficult to determine as the harvest varies from 9 months to up to 4 years from planting or ratooning. Therefore, various sampling practices are conducted in different areas.

  A common practice is to use the leaf-blade lamina (midrib removed). The leaf selected is often the third (3) from the top of the plant. Some agronomists identify this leaf-blade by finding the uppermost leaf which has a distinct collar on the stalk termed "top-visible dewlap leaf."

  A system of "crop logging" developed in Hawaii (Clements 1980) utilizes the leaf sheaths from the 3rd to the 6th leaves from the top of the plant for P, K, Ca and Mg and the lamina of the leaf blades from the same leaves for N. Another sampling procedure utilizes stalk internodes number 8 to 10 from the base of the stalk (Hawaiian Sugar Planters Association).

  Care must be exercised to standardize the time of day that samples are collected. Thein and Gascho (1980) found that concentrations of N, P, Ca and Mg in leaf samples decreased significantly during the day (Table 1). Early morning sampling is preferred (Clements 1980).

  Table 1. Mean tissue nutrient concentrations in sugarcane TVD leaf blade laminas as a function of time of day § †
  Time of Day	Plant Tissue Nutrients>
  	%N	%P	%K	%Ca	%Mg
  8 a.m.	2.03	0.24	1.41	0.28	0.20
  11 a.m.	1.97	0.25	1.40	0.27	0.19
  2 p.m.	1.88	0.23	1.38	0.26	0.18
  5 p.m.	1.80	0.22	1.40	0.25	0.18
  Significance ‡	**	**	NS	**	**
  § Source: Thein and Gascho (1980). † TVD = top visible dewlap. ‡ The 1% level of significance of linear regression is indicated by **. NS = not significant.

• Sufficiency Ranges
  
  
  • Top Visible Dewlap (approx. 3rd leaf blade lamina)
    
    

    Macronutrients
    N	P	K	Ca	Mg	S
    2.00–2.60%	0.22–0.30%	1.00–1.60%	0.20–0.45%	0.15–0.32%

    
    

    Micronutrients
    Fe	Mn	Zn	Cu	B
    50–105 ppm	12–100 ppm	16–32 ppm	4–8 ppm	10–50 ppm

  • Hawaiian Systems
    
    

    Macronutrients
    	N	P	K
    Crop logging, leaf blades 3–6, lamina	1.85%
    Crop logging, leaf sheaths 3–6		0.08%	2.25%
    HSPA, internodes 8–10	0.24–0.35%	0.03–0.04%	0.7–1.0%

• DRIS Norms
  
  DRIS norms have been developed in several areas. The crop has been shown to respond well to "in crop" corrections made following DRIS analysis. The norms developed in Florida on muck soils are quite similar to those developed in South Africa on mineral soils (Table 2).
  
  

  Table 2. Sugarcane TVD leaf blade lamina norms from Florida and South Africa § †
  Nutrient Ratio	Florida	South Africa
  N/P	8.706	8.197
  N/K	1.526	1.511
  K/P	5.633	5.464
  Ca/N	0.151	0.128
  Ca/P	1.314	1.146
  Ca/K	0.222	0.205
  Ca/Mg	1.373	1.158
  Mg/N	0.113	0.116
  Mg/P	0.984	0.962
  Mg/K	0.163	0.186
  § Data from Beaufils and Sumner (1976) and Elwali and Gascho (1983). † TVD = top visible dewlap.

• Remarks

  The critical values and sufficiency ranges presented in this paper are not absolute for all sugarcane. They are heavily based on the author's studies on the muck soils in Everglades Agricultural Area of South Florida and on the top-visible-dewlap leaf blade lamina collected in the early morning. Muck soils enhance N uptake. As a result, N concentrations in varieties grown in Florida are generally higher than those produced on mineral soils in other areas.

• References

  Beaufils ER, Sumner ME. 1976. Application of DRIS approach for calibrating soil and plant factors in their effects on yield of sugarcane. Proc S Afr Sugar Technol Assoc 50:118–24.

  Clements HF. 1980. Crop logging of sugarcane—principles and practices. Honolulu (HI): University of Hawaii Press.

  Elwali AMO, Gascho GJ. 1983. Sugarcane response to P, K, and DRIS corrective treatments in Florida Histosols. Agron J 75:79–83.

  Evans H. 1965. Tissue diagnostic analysis and their interprepation on sugarcane. Proc Int Soc Sugar Cane Technol 12:156–80.

  Gascho GJ, Elwali AMO. 1978. Tissue testing of Florida sugarcane. Gainesville (FL): University of Florida Institute of Food and Agricultural Sciences (IFAS). Belle Glade Agricultural Research and Education Center Research Report EV-1978-3.

  Gascho GJ, Anderson DL, Bowen JE. 1993. Sugarcane. In: Bennett WF, editor. Nutrient deficiencies and toxicities. St Paul (MN): American Phytopathological Society Press.

  Srivastava SC. 1992. Sugarcane. In: Wichmann W, editor. IFA world fertilizer use manual. Paris (France): International Fertilizer Industry Association.

  Thein S, Gascho GJ. 1980. Comparison of six tissues for diagnosis of sugarcane mineral nutrient status. Proc Int Soc Sugar Cane Technol 17:152–62.

Electronic Document Prepared by:
Catherine Stokes, Communication Specialist
Agronomic Division of the N.C. Department of Agriculture and Consumer Services. July 2000.