Nutrient Uptake- by plant WPS Office-1.pptx

Nutrient uptake

1. Nut rient Uptak e By Pla nt Roots M o v e m e n t o f N u t r i e n t I o n s I n t o T h e R o o t S y s t e m

2. Nu tr ient Up ta ke T h i s i s t h e a m o u n t o f e a c h n u t r i e n t r e q u i r e d f o r a c r o p t o c o m p l e t e its life c y c l e a t a g i v e n y i e l d l e v e l . It r e f e r s t o p r o c e s s e s n e c e s s a r y f o r m o v i n g a n u t r i e n t ( d e n o t e d a s a n i o n ) f r o m t h e s o i l s o l u t i o n b y r o o t s i n t o t h e plant s y s t e m ( o r t o a s i t e w h e r e f u r t h e r p r o c e s s i n g o f t h e i o n t a k e s p l a c e ) . P l a n t r o o t s p e r f o r m d o u b l e f u n c t i o n s o f a n c h o r i n g t h e p l a n t s f i r m l y t o t h e s o i l a n d a s o r g a n s f o r n u t r i e n t a n d w a t e r a b s o r p t i o n .

3. T he re a re s ix te en n ut ri en ts t ha t ar e es se nt ia l fo r pl an t gr ow th a nd d ev el op me nt . Th ir te en a re a bs or be d by t he roots. A ft er t ak en i n by t he r oo ts ,t he n ut ri en ts m ov e in to t he p la nt a nd a re u se d fo r various f un ct ions a nd p ro ce ss es . N ut ri en t up ta ke , ab so rp ti on a nd utilisation is n ot a s im pl is ti c pr oc es s. There are essentially two phases. First, the nutrient must reach the root surface , th en i nt o th e ro ot s ys te m an d la st ly , must move into cells of the plant .

4. Plants don't necessarily grow in search of plant nutrients. Nutrients must ge t to the plant root to be absorbed by the large numbe r of root hairs.. Root hairs live in association with a diverse group of fungi called mycorrhiza e which aid the movement of nutrients from outsi de (the soil solutoon) to inside of the root itself. A nutrient element t hat is to be absorbed must be in a soluble form and mus t be located at the root surfaces, or within the area of the soil immediately surrounding the root hair.

5. Mov ement of Ions fr om soil to root surfaces Th er e ar e th re e me ch an is ms o r ph ys io lo gical m ed iu ms b y wh ic h pl an t ro ot s ac qu ir e nu tr ie nt s from s oi l sy st em . Th es e me di um s fa ci li ta te t he t ra ns fe r of n ut ri en ts o r io ns t o th e su rf ac e of r oo t ha ir s. . Th e va ri ou s mechanisms c an o pe ra te i n th e up ta ke o f si ng le nutrient , bu t th ei r si gn if ic an ce i s re la y on t he r el at iv e po rt io n of n ut ri en ts i n th e pl an ts a nd s oi l. Th e th re e me ch an is ms r ec og ni sed a re a s fo ll ow s; R oo t in te rc ep ti on ( Co nt ac t ab so rp ti on ) ma ss f lo w an d di ff us io n.

6. Ro ot i nt er ce pt io n (c on ta ct a bs or pt io n) T h i s o c c u r s d u e t o t h e g r o w t h o f r o o t s t h r o u g h t h e soil mass t h e r e b y c o m i n g i n c o n t a c t w i t h i o n s i n the s oil a n d increasing t h e o p p o r t u n i t y f o r i o n a b s o r p t i o n . T h e r o o t s t h e n a b s o r b s t h e n u t r i e n t s . N u t r i e n t a b s o r p t i o n t h r o u g h t h i s m e c h a n i s m i s t e r m e d - c o n t a c t a b s o r p t i o n o r f e e d i n g . I t i s a n i m p o r t a n t m o d e o f t r a n s p o r t f o r c a l c i u m ( C a ) a n d m a g n e s i u m ( M g ) , b u t i n g e n e r a l , a minor p a t h w a y f o r n u t r i e n t Ions t r a n s f e r .

7. M as s fl ow T h i s o c c u r s a s a r e s u l t o f transp i r a t i o n a l u p t a k e o f w a t e r b y t h e p l a n t . I t i s t h e m o v e m e n t o f d i s s o l v e d nutrients i o n s i n t h e f l o w o f w a t e r t o t h e root s u r f a c e a s the p l a n t a b s o r b s w a t e r f o r t r a n s p i r a t i o n . I t i s r e s p o n s i b l e f o r m o s t t r a n s p o r t of n i t r a t e s , s u l f a t e , c a l c i u m a n d m a g n e s i um . M o v e m e nt o f n u t r i e n t b y m a s s f l o w i s r e d u c e d a t l o w t e m p erature a n d a t l o w moisture c o n t e n t .

8. D i a g r a m 1 ; s h o w i n g t h e m a s s f l o w m e c h a n i s m o f n u t r i e n t i o n s t o r o o t s y s t e m

9. D iffusion T h i s i s t h e m o v e m e n t o f n u t r i e n t Ions a l o n g a c o n c e n tration g r a d i e n t from h i g h e r c o n c e ntration t o a l o w e r c o n c e n t r ation a r o u n d t h e r o o t s u r f a c e . T h i s i s a continuous p r o c e s s . N u t r i e n t i o n s d i f f u s e t o w a r d s t h e r o o t s when i o n c o n c e n t ration a t t h e r o o t s u r f a c e s d e c r e a s e a s p l a n t a b s o r b nutrient , t h e r e b y c r e a t i n g a n u t r i e n t c o n c e n tration gradient . M o s t p h o s p h o r u s a n d p o t a s s i um ions m o v e b y d i f f u s i o n .

10. T h e r e a r e f a c t o r s t h a t a f f e c t t h e r a t e o f d i f f u s i o n o f i o n s t o t h e r o o t s u r f a c e ; percentage of clay size particles in the soil, the rate of nutrient applied in a fertilizer program, and the placement of the fertilizer (band or broadcast). Diffusion is slow but continuous as long as the plants are growing.

11. D i a g r a m 2 : S h o w i n g t h e m o v e m e n t o f n u t r i e n t i ons v i a t h e t h r e e m e c h a n i s m ; r o o t i n t e r c e p t i o n , m a s s f l o w a n d d i f f u s i o n .

12. M ov em en t of I on s In to T he R oo t Sy st em The move ment of nut rien t io ns from root sur face int o th e ro ot c an b e de scri bed be t wo p rocesses : P a s s i v e m o v e m e n t / t r a n s p o r t a n d a c t i v e m o v e m e n t / t r a n s p o r t . P a s s i v e m o v e m e n t / t r a n s p o r t Passive transport means that the ions are carried with the uptake of water into the plant without e x p e n d i t u r e o f m e t a b o l i c e n ergy from the plant.

13. T h e water movement factors that affect passive transport are temperature, humidity, photosynthesis rates, concentration of ions in solution versus within the plant cell, and plant transpiration rates based on stage of growth. Passive transport occurs in the root's free space (cell walls) and is kinetically controlled by diffusion and mass flow, with ion exchange occurring between the solution and the negatively charged cell walls.

14. P a s s i v e t r a n s p o r t s i n v o l v e s s i m p l e d i f f u s i o n a n d facilitated d i f f u s i o n . S i m p l e d i f f u s i o n e n tail s the movement of i o n s from a region of higher concentration to a lower concentration. The difference in the concentration of the two areas is termed a concentration gradient and the process of diffusion continues until this gradient neutralizes o r r e a c h es e q u i l i brium .

15. Facilitated diffusion is a type of passive transport that allows ions to move into the root with the assistance of transport proteins. It is a crucial process that enables plants to absorb essential nutrients from the soil. It involves; I o n channel s : Specific ion channels in the root cell membrane allow ions to pass through. C arrier proteins : Carrier proteins bind to ions and transport them across the membrane. C oncentration gradient : I ons move down their concentration gradient, from high to low concentration. E n ergy-independent : No energy is required, as the ions move passively.

16. D i a g r a m 3 : P a s s i v e m o vement / t r a n s p o r t o f i o n s i n t o t h e r o o t s y s t e m

17. A c t i v e m o v e m ent / t r a n s p o r t T h i s i s t h e m o v e m e nt of nutrient ions into the root system involv i n g t h e use of energy by the plant to absorb nutrients against their concentration gradients. This process is essential for plants to obtain essential nutrients, especially when they are scarce in the soil.