• No symptoms of nutrient deficiency or toxicity from tillering to early panicle initiation (EPI) and flowering.
• Achieved at least 300 panicles/m2 (TPR) or 350 panicles/m2 (DWSR) at dough stage.

How to assess the number of panicles at dough stage:

1. Randomly select three sampling sites (1m x 1m quadrat) at least 1m from the dike and in a diagonal line across the field.
2. Count the panicles in each quadrat and get the average panicles/m2.

 

1. Know and manage the nutrient requirements of your crop based on:

a. visual observation of deficiency symptoms

Tips in proper visual diagnosis of nutrient deficiency

b. results of nutrient diagnostic and decision support tools:

Diagnostic and Decision Support Tools

Leaf Color Chart (LCC)
A tool to visually assess the nitrogen status of the rice crop.

 

 

Minus-One-Element Technique (MOET) and MOET App
A pot experiment that is complemented with an ICT-based application to
determine the nutrients deficient in the soil and the amounts needed for a certain
target yield.

 

 

 

Nutrient-Omission-Plot Technique (NOPT)
A means to assess indigenous nutrient supply to serve as basis of
fertilizer recommendation.

 

 

Rice Crop Manager (RCM)
An ICT-based platform for rapidly deploying improved nutrient
and rice-farming management technologies.

 

 

 

 

c. other available information such as data obtained from extension workers or rice specialists

2. Know the right element, amount, and timing of fertilizer application. Make E-A-T right.

E – Know the right nutrient ELEMENT that the plant needs. Giving the right nutrients increases cost efficiency and attainment of target yield.

A – Know the right AMOUNT of fertilizer to apply. Too much or too little is not good.

T – Know the right TIMING of fertilizer application to increase efficiency in input cost and nutrient uptake.

NITROGEN (N)

Right element. N promotes rapid growth for increased:
• plant height, tiller number, and leaf size;
• number of panicles per hill;
• number of spikelets per panicle;
• grain protein content; and,
• percentage of filled spikelets.

N deficiency results in stunted, yellowish plants; older leaves or whole plants are yellowish green.

 

Excessive N during panicle initiation and flowering:
• makes the plant prone to lodging and pests;
• increases unfilled spikelets;
• is costly and may contribute to environmental pollution.

Right amount. Use results of LCC, RCM, NOPT, and MOET/ MOET App as basis in properly determining the amount of N to apply.

Right timing. If LCC is available:

• use LCC every 7 days from 14 DAT or 21 DAS until early flowering
• apply N if 6 or more out of 10 leaves are below 4 (TPR) or 3.5 (DWSR).

If LCC is not available:

	Application
	1st	2nd	3rd
For ≤ 110-day maturity	0-14 DAT or 7-10 DAS	5-7 days before panicle initiation
For > 110-day maturity	0-14DAT or 7-10 DAS	midtillering	5-7 days before or after panicle initiation

 

PHOSPHORUS (P)

Right element. P functions mainly for energy storage and transfer. In rice, it promotes vigorous root development, tillering, and early flowering and ripening.

Deficiency symptoms include:
• stunted dark green plants with narrow, short, very erect leaves and greatly reduced tillering;
• thin stems and retarded development; and,
• reduced number of leaves, panicles, and grains per panicle

 

Right amount. Use results of MOET/ MOET App and RCM as basis in properly determining the amount of P to apply.

Right timing.

	Application
TPR	0-14 DAT
DWSR	7-10 DAS

 

POTASSIUM (K)

Right element. K in rice plants:
• speeds up root growth and boosts plant vigor;
• accelerates uptake of other nutrients;
• improves tolerance of rice to adverse conditions such as pest and disease infestations, drought, lodging; and,
• increases grain size and weight, and percent filled grains

K deficiency is often not detected because its symptoms do not appear until the later growth stages, and are not as easy to recognize as those of N deficiency.

K deficiency symptoms include dark green plants with yellowish brown leaf margins or dark brown necrotic spots first appearing on the tip of older leaves. Yellowing follows a “Ʌ” pattern and progresses downward if deficiency is not corrected.

Right amount. Use results of MOET/ MOET App and RCM as basis in properly determining the amount of K to apply.

Right timing.

	Application
	1st	2nd
TPR	0-14 DAT	5-7 days before or after panicle initiation
DWSR	7-10 DAS	5-7 days before or after panicle initiation

 

ZINC (Zn)

Right element. Zn promotes good seedling and overall growth of plants. It is essential for several biochemical pathways and structural processes in the rice plant.

Zn deficiency symptoms include dusty brown spots on upper leaves of stunted plants appearing 2-4 weeks after transplanting. In Zn-deficient soils, NPK fertilizers alone cannot provide good yield unless the deficiency is corrected.

 

 

Right amount and timing. Use results of MOET and RCM as basis in properly determining the amount of Zn to apply.

If MOET or RCM are not available, choose only one among the following amelioration techniques:

	AMELIORATION TECHNIQUES	AMOUNT	TIMING
TPR	Seedling dip	2% ZnO solution	dip for 15-30min
	Seedbed	apply 0.5-2kg per 400m2 seedbed or 0.5-2kg per 40kg inbred seeds	seedbed
	Broadcast	25kg ZnSO4/ ha	10-14 DAT
	Foliar spraying	2% solution spray (volume spray of 170L/ha)	14 DAT
DWSR	Seed Zn coating	1% of the dry weight of seeds	seed preparation

 

SULFUR (S)

Right element. S in rice plants:
• promotes uniform growth and maturity;
• speeds up chlorophyll production, protein synthesis, and plant function and structure; and
• reduces yield if deficiency occurs at vegetative stage

Symptoms of S deficiency include yellowing of young leaves, less tillers, fewer and shorter panicles, reduced number of spikelets per panicle, and delayed maturity.

Right amount. Use results of MOET test or RCM as basis in properly determining the amount of S to apply. The amount of S in 14- 14-14-12S (12%S) as recommended to treat P and K deficiencies is adequate to correct usual S deficiency.

Right timing.

	Application
TPR	0-14 DAT
DWSR	7-10 DAS