LOOSE SMUT OF WHEAT.
II. FIELD EXPERIMENTS ON SEED-DISINFECTION BY HOT WATER.
J. C. NEILL,
Assistant Mycologist, Biological Laboratory, Wellington
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(4.) Without previous soaking only partial control was obtained by dipping for ten minutes up to 135 0 . (5.) A soaking for twelve hours- in water maintained at 104° gave complete control of the smut, with a loss' of 8-2 per cent, of mature plants as compared with adjacent untreated controls. f r (6.) The effects of the treatments on germination of the seed are not so clearly defined as are the effects on the smut, owing, in all probability, to the -generally'low and irregular germination .due to the dry period following sowing (see Table 7). A certain improvement in germination over controls is apparent at temperatures', of dip below the critical point for complete killing of the smut, but above that point there, is a loss in germination which increases with both the time and temperature of dip. All the experiments show, however, that it is possible to obtain, within practicable temperature, limits, complete freedom from infection, with a loss in germination of less than 10 per cent. ... : (7.) The field germination of wheat' is not materially affected by delaying sowing up to at least four months after treatment and drying. (8.) The amount of loose smut present in the wheat stand appears to have no correlation with external’ conditions such as temperature, rainfall, or date of sowing, but to depend solely on the amount of infection‘ present in the seed. . ...
The : meteorological records were kindly supplied by Mr. H. P. Clayton, Curator of the Ashburton Botanical Gardens and Meteorological Station. The records were taken two miles from the site of the experiments. The figures given under “Mean Temperature ” are the arithmetical mean for the week of the daily maxima and minima. The writer wishes to acknowledge gratefully the help rendered in this work by Mr. J. G. McKay, Overseer of the Ashburton Experimental Farm, who carried out the weekly sowings recorded in Table 7, and whose practical assistance, has proved invaluable throughout the whole of the experiments. The writer’s thanks are also due to Mr. N. R. Foy, Seed Analyst, and his assistants, who carried out the laboratory germinations here recorded.; and to Mr. F. E. .Ward, Instructor in Agriculture, for co-operation in providing facilities for the work.
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* In these two sowings the seeds were planted i in. apart, 400 seeds being sown instead of 200 as in the other sowings of the series.
Control Co o Control Co o Control A CO o Control HM to <0 o Control to o Control A to Cn o Control to Co c Control Ft to O Control Control M co Cn o Control Co CO o Control CO 0 Control to 0 Control to . 0 Control. •to Cn 0 Control to CO. 0 Control to 0 Control Temperature of Dip. Cn o Control Co Co 0 Control A Co o Control °o Control to o Control to o Control A to Co c Control 5 0 Control Control co 0 Control A CO O Control CO 0 Control to vO 0 Control 127° .. Control to Cn 0 Control to 0 Control to 0 Control Temperature of Dip. © © © KO ©, © © <0 KO © © © KO © KO © KO v0 VO KO © © © © © © © © © © © © © cO (JO 00 Ln OO 00 C\ OO oo CO KO CO OO 00 00 00 O CO CO Ln 00 Co -GO Cn 00 C0 00 ch 00 ■4 00 Laboratory. ©O (JO Cn do 41 00 Ch (JO oo OO © oo GO 00 co 00 O (X) 44 OO Cn (JO Co vJO Cn OO © C/0 Ch 00 41 OO cn 0 Ln Co Ln 41 Ln 41 Ln o Cn. co Cn 41 Ln Co Ln Cn o Ln 4} Ln 6 Cn 41 Cn CO Cn CO Cn 41 Cn 41 Cn CD — fX Co Ln ■ |x 44 (0 44 44 Co CO CO CO 44 CO CO CO Cj} Co 44 44 First O CD P ,f\ Co Ln 4x ’ 4x "to -fX fx Co tx fx OJ co CO CO CO _|X co co CO f .o co fx fx fx .fx fx First 0 y On >— < Ln c p -fX fx OK Cn - fx <0 Cn to 00 Ch Ch © to CO ch (X) cd K0 0 - fx _ fx GO r-H 6 Cn d •©d 6 6 Ci Ln 41 Cn to Cn 6 Cn Cn 6 6 p6 to 6 Cn 6 Cn Cn 0 0 6 Cn Cn Cn Cn Count. co tTQ a> O Hi Cn Cn 44 44 Ch Cn to Ch 44 O Cn to co 0h ©d Oh © to co © co co vO 0 44 00 ■©d o -fx ■ fX CO fX JX. CO CO ■ fx, fx CO CO CO HH co co co CO CO fx CO CO CO CO CO co Co CO K fx Mature 0 o 6 Cn o Ch Cn 41 Ln to Cn o Cn Cn 6 41 6 CT 4 6 to 6 41 Ln 0 Cn Cn 0 4t 6 41 6 Cn Cn Cn Cn & Count. 0Q CD o to Ch Co oo 00 o co Hi Hi CO oo O\ co O Cn © H OO Cn *d 00 Cn Cn 4x *4 to OO Cn •4 2 00 ~oo o co -L Zo CO Ch 4 0 Cn O CO % co w 44 *4 Co OO CO Co Cn CO co '’to 'co Cjl Mature 3 Germin o o Ln to o 41 o o to o to Cn Cn 0 Cn 0 CD W 6 0 Cn 0 Cn 0 Cn 0 O to O 41 6 6 6 td Cn CD cn Plants. O O 41 o to o to Cn Cn o Cn 6 O W 6 o Cn o Cn 0 Cn 0 O to 0 *4 0 0 0 to Ln 0 cn Plants. ’ 2 y. p‘ O O p 1 1 © 1 1 © + N 1 + + CO P O to bO 1 1 + O + O 1 CH + bO p tr <T> Gain or Loss over tion ►E» + + CO Q 1 M to f 1 >F* + © + O 1 ox + to p fc0 Gain or Loss over Adjacent Controls. tion. to © co w o Ox w Or p-> 61 61 tsS to 61 6i CL Adjacent Controls. *4 Ox CH to *4 to dx 6x p-» Tl co © © Ln KO Ch 00 Ch 00 •<1 4x 00 Ch xq Cn d < co Co dj Ln CO CO 01 •4 to »4 00 © << Total. di CO ©d CO ■©d 00 CO 4) _K 44 to 41 00 V0 Total. o 00 CO CO ch Co © 41 to CO © Cn 41 to o CO 44 Ch © Ch Cn to Co Ch 0 H 00 CO co 01 1-1 Ch Cn to co © 0 co co 44 CO Ch Ln O O •u 1 X H Hi to to hi i— < to to j—i tn H Hi M to Hi Hi Hi Hi Hi f 0 to cn Si o CO o o to o to to H 4 VO © to 0 to Cn co cn x’ 00 H Co 0 0 to CO 4; to Cn VO o> CO co CO Six Smutted. lants Hl HI Hl to to to H, to to K to to to to to bD to bD K o 00 o o o to *4 H © Ch o Cn 00 £" 00 CO o 0 **4 CO *4 to Cn © Oi GO 00 41 Cn X 5H •*d Hi to to to Hi to to K to to CO to to Hk to FO to ro to ffi © VO © *4' © co © Ch © to © o © 00 Ox CO © 00 © to © to to 44 to w 01 Co 0 © 0 Percentage M. to co OX GO © 01 .Percentage Cn 44 41 c 00 CD 4* -4 Co © © 00 co w 41 *4 Cn to Co co © 00 *4 cn Smutted. M H*4 44 41 Ln to CO do Ch 00 41 L. 44 cn Smuited. p H H p . -fx © - fx - CD ■di -[X 00 CjJ co co © Co di to © ( A) 44 00 ,y\ [X © Cn © , [X, © (jl CO _[X O ..[X O (JI Total - fX -fX OO CO 00 Co 01 Co to OK co CO © Cn © _ fx © ( p 00 -fx O _fx 0 Cn Total Ca) o co o 44 di dl i— i co Q © v© © O'* V0 Cn Ch 44 0 kO 0 44 Ch Hl 0 © **d CO Ch ch KO 41 M Cn to 4r 0 O'* 44 to Cn 44 0 © 41 to 44 41 Co Ln to to 00 00 CO 41 44 to 0 Hi K Ln *»4 Ln O © Ch ©0 0 © 00 Ch © j— 1 © •>»d Ln HI 00 © © 00 ( Al 0 4f to Ch o to o CO O Ch o Cn to co 44 44 CO to Ch. 41 O 4r 0 (JO 0 © © © 00 44 0 CO 0 to & to o Ln © Co © to O © JO © Ch © 00 co to Jit co to O HX Ch © 5 0 to co co © co 4? Ch 00 to to OD to Percentage CO O to 4VO to to cd Ch W 0 -4 do Oi tvO 41 to Si <1 41 co to 00 Cn 44 smutted. Hl ro IO ro M H to HI to ha M Hk M H< ro M Hl bO Hl bO Hl bO to to bO Hl b3 to V0 bD O o vO CD CO © 44 © Ch di 00 4J f-H Cn 44 co 0 Ch w V0 CO CO M 00 0 N> CO to Sound Heads harvested o *4 44 CO 41 CO t-4 CO co 0 Oi cn W to Ch © 4J 00 44 00 44 44 co bo to 4J © to CD 0 per 100 Seeds sown. o 00 o -fx d Hi oo o KO C0 KO <h © © Cn Ch -{X o kO 0 CO 01 H 0 © 4J CO Ch Ch w 41 K H Ln to 4t o OK to Cn o o. to 44 Co Cn to to 00 00 *4 CO *4 M to 0 K ( Ln tjl o CO Ok co o Oi CD 01 KO Hi 01 *«d Ln Hi GO V0 01 00 CO 0 *4 to p xjj o to o 00 o Ch o Cn to co 4x CO to H . OK ■"d o **d 0 00 0 01 Ct © 00 0 co *4 0 to ex Q> H o Ln © CO o to o © 42 © w Ch © 00 co to 00 to O Hk © © © © to CD 5) © 00 “4 3i w to to s to Percentage to 00 to KO to to co Ok co o *4 do cS to *4 to ST <1 *4 00 to 00 Cn 4T smutted. o ro to K> M HX M to Hi to Hk M ha M M M to H| HX Hi bO H| to Hi ho to Hk. to bD Hi bD to Hi V0 o © KO © 00 o _fx o Ok ■4 00 ■4 Hi ox 4* oo Cl © Ch w kO ca GO M 00 0 to 00 to Sound Heads harvested bo *4 -£*■ M co 41 4* Co CO co o O( Ch w to o> © 00 co 00 to to •*4 Cn © to O 0 per 100 Seeds sown. o
Table 1. Seed Wheat dipped Three Minutes.
Temperature of Dip. Percentage Germination. Plants. Heads. harvested Seeds per Laboratory. . Field. Total. Smutted. Percentage Smutted. Total. Smutted. . Smutted. Percentage Percentage smutted. First Count. Mature Plants. Gain over Adjacent Controls. Total. (a? Presoaked Five 1 Five t 0 Six Hours 0 Six at 63° Hours at 63° Control 98’5 ’ 38-0 38-0 76 18 23'7 469 97 20-6 186 121° .. 96-3 36-5 34-2 — 0-3 137 26 19-1 760 106 13-9 163 Control 98-5 31-5 31-0 62 19 30-7 393 103 26-3 *45 123 0 .. 973 39-7 35-o — 3-7 140 . 15 10-7 . 859 54 6-3 201 Control 98-5 50-5 46-5 93 27 29-0 540 160 29-7 190 125° ... . 97-3 .46-5 ’ 40-2 —2-5 161 6 3-7 980 13. , 1-4 242 Control 98-5 4°'5 39-o 78 .18 23-1 . 4 T 9 . 82 19-6 168 I2 7 ° . . 97-° 34'° 30-2 —8-8 121 0 0 694 0 0 173 Control 98-5 4 T ‘5 39-o 78 23 29-5 429 114 26-5 x 57 129 0 ' .. 93-3 41-0 37-7 — 3-9 *5* 0 0 881 0 0 220 Control 98-5 47'5 44-2 89 • 22 24-7 47 6 124 26-0 176 *3*° •• 92-3 39’7 37-o -8-3 148 0 0 702 0 0 175 Control 98-5 50-0 46-5 93 19 20-5 . 406 75 18-5 165 T 33° • • 85-3 44'2 42-2 — 10-3 169 0 0 686 0 0 171 Control 98-5 64-5 58-5 117 30 25-6 532 125 23-5 203 *35° ’ •• 50-7 10-2 10'7 -33-8 43 1 2-3 213 3 1-4 52 Control 98-5 35'0 30-5 61 11 18-0 326 35 io-8 *45 [(&.) Presoaked Five 1 0 Six Hours at 84° Control 98-5 41-0 40-0 80 14 *7-5 436 56 12-8 190 121° 96-3 41-0 38-5 + 0-3 154 20 130 851 84 9-9 192 Control 98-5 39-5 36-5 73 17 23-3 424 87 20-5 168 123° 95-7 43-2 40-0 4-4-3 160 5 31 869 13 1-5 214 Control 98-5 39-o 35-o 70 18 25'7 397 83 20-8 *57 125 0 •• 98-0 33’0 30-5 -3-0 122 0 0 737 0 0 184 Control 98-5 36-0 32-0 64 12 18-8 366 47 12-9 *59 127 0 .. 98-3 44'2 40-7 -70 163 0 0 800 0 0 200 Control 98-5 66-o 63-5 127 25 19-7 646 107 16-3 269 129 0 95-3 49-2 43-5 -13-0 *74 0 0 889 . - 0 0 222 Control 98-5 56-5 49'5 99 22 22-2 548 117 21-4 215 *3*° .. 95-o 47’7 42-2 — 10-3 169 O 0 778 0 0 194 Control 98-5 56-0 55'5 in 26 23-4 543 104 19-2 219 133° • • 877 31-2 29-0 -19-5 116 0 0 601 0 0 150 Control 98-5 43-o 4 i ’5 83 25 30-1 4°3 109 27-2 147 135° • • 68-o 11-2 io-7 -28-8 43 O 0 267 0 0 67 Control 98-5 4 -5 37’5 • 75 75 17 *7 22-7 22-7 422 422 85 85 20-2 20-2 168 168
Table 2. Seed dipped Five Minutes.
to to P. • - y y y S ts p 5. ; p . • p. p, 0> O Bi. -. X < ‘ - . o /, .... . 4 4 . .kO<JkOkOk£>kOkOkOkOkOkOkOkOkOkO © © ©>©-©' ; p p w -4 co Temperature of Dip. lOMiO'OO'O'O'O'OiOiOiO'OO'O IO IO O O Laboratory. Percentage Germination. 4*- p tiln4Oi'444ln W w w 6 6 Co © to pi p Laboratory. Percentage Germination. Cn J- -4 -fx OOO.NOlnOtjuknONO F 5 First Count. Field. ' to Ci , ui 4 to t-i tri + P p h? p 4 First Count. Field. Co. co hh 6 6 $ Mature Plants. 4 p to p ip I £ i. . L 6 t Ci d $ <J> S' pl • • • pv Mature Plants. .+.1.1' & i i I tL.Jx.i.i. cn to w Gain or -Loss over Adjacent Controls. ’ ...... . -‘p ® pl - • p- p- 5’ " 10 HI . ; <?' dioododotb do w P -O © O Gain or Loss over Adjacent Controls. P tp Cn©t0©t0CnCOMOHiH4 Total. 35 w • P‘ W . <’ o o ■ ■ ■ . .. . 6 to to' ' to . tp co O -4 Op P Total. Smutted. Plants. O - Q td ■ CZ>W to to to '■ ; 'to to to to o 10 O © © pl g Smutted. td 6 y CO . 1 to to to Q cn cn . Percentage ’ Smutted;. . Oto g 1 • y p dr o 3 * 4 co 4 w cn Qi' 4 CO to Percentage Smutted. 5* P £0 t04k-4k CO 4 O' r± UiCidUiOO'+OOCiOOiO+Oo+ + .O'- ' Total. .Heads. - CnC0t0*d'OCn00C0HMCn00t0 00 cn ' Ok 4c to to co O O Ok n Smutted., ” ° ° . 'to to to • • . to Total. Heads. 0 N co •CIOtOOHOOO & to CX?00.6o Smutted. Percentage . smutted. ’tO to to MtOtOtOMtOto t->kH H M>-»kM>-ikM fcOtOrO 00000*<rOCoC>MO>-;00 Cn cn 6 h 00 co Cn Cn Op (X) do Percentage smutted. M \o co to co o oo to -q m cn o cc> cn + Ci OO 05 OO t0CDOWHW+lO+ CD CO 4i Sound Heads harvested per roo Seeds sown. 'sOWIOOOHO)^tO<|HCn0>C0O' 1 CO N harvested Sound Seeds per
Table 3. Seed dipped Ten Minutes.
co O ' - O 333333 ° ° o o o o 3, 3 ; ; 3, Temperature of Dip. S S .P CTkOkOkOkOkQkOkOkOkO KO 3 3. ; ; ■ ; CT CT Temperature of Dip. Qi.iO.OiOiOlO'OO'O'O Ci CT CT Laboratory. Percentage Germination. ooGooUioootopwoo. -o U4kWWWU)WWWWCT ui <ji Ln W (Ji W CT CT s Laboratory. Percentage Germination. CT CT 6 6 6 to CT CT CT CT o First Count. Field. 4- IJ 'JJ 4 ti CT CT 15 CT tO '.J H w -J CT COO CT KO CT KO CT CT 6 6 CT CT CT CT CT N> 6 Mature Plants. • w ■ i • 1 . + . + . • to • O • CO • O • -q tb W <1 O Gain or Loss over Adjacent Controls. <0 CO 00 CT CT CT CT CT CT CT CT CT to CO CT CT w CT KO CT 00 Total. Plants. to m 10 tO »H tO w CO tO tO M iO Smutted. to to h to to co to to Ok O Cn 00 -4 cb 6> di <6 A co 6 6> co Percentage Smucted. M H H H Cn ChCn OCn O Cn tOCn m ChMHHrHi-<tOCO*<J>-lkO to *<r to O Co kO Ok to Cn co Total. Heads. iOkO to m Ok Ok Co' <O Cn O) to O to to O t: Cn 4 M co Ok Smutted. o 6k A -i- Ch <i 4I 0 co Percentage smutted. t-OCTHtototOMbOtOWW tv to KO COW CT 0 05 0 w -< 0 45 CT CT CT CT CT OCT CT h Sound Heads harvested per 100 Seeds sown. ' ■ w s First Count. Field; ti Qi O 6 6 to' CO CO <0 co Co- (Ji to 6 MaturePlants. Jo 1 • . . Gain or Loss over Adjacent Controls. 4 ■4 W ■ -U CT. IO H 3 2f G Total. tOMtOtOM -4 • K . Smutted. tO to to ■ c Percentage Smutted. i Cn IO O ' O to to ; Heads. Total. ; to co Ok Smutted. ■4 w Percentage. toM-HtototsoHtowroK) Sound Heads harvested per ioo Seeds sown. O -COLII »f»Oi>jp»Cn O "<r H
Table 4. Seed dipped Ten Minutes. No Presoak.
F" Control Treated Control Temperature of Dip. o 00 6 Ln Laboratory. Percentage Germination. "o 6 Ln First Count. Field. ' In W 6 Ln Mature Plants. O to -100 Mature Loss Plants. compared with Controls. 1 O CO Total. Plants. o • .10 bO o O Smutted. Loss compared with Controls. M to 00 © Total. Plants. "• to Ln Percentage smutted. O O Ln kO Smutted. to Ch O O' o Total. Heads. Ln to Percentage smutted. Ln . kO 0 o Smutted. to ■ o 10 O to © Total. Heads. ’ ' to kO 00 Percentage smutted. 0 o 220 Smutted., . to 237 O 212 Sound Heads harvested per loo Seeds .sown. Percentage smutted. 6o ' e . to co to o harvested Heads Seeds per
Table 5. Test of Deterioration of Seed after Storage (treated 8th May, sown 11th September): Presoaked Six Hours at 63°; dipped Ten Minutes at 127°.
■ Control 98-5 55-5 47'5 - . ■ 95 ■ 1 95 ; 16 16 16-9 16*9 469 469 77 77 i6'4 . 16*4 196 196 Treated 95-7 48-0 41'5 8-2 ,166 ' 0 0 797 0 0 199 _ Control 98-5 55'° 52-0 104 33 31'7 • 479 139 29*3 168
Table 6. Seed soaked for Twelve Hours at. 104°.
g-i2 Sept. to to HI co to to i_i hi to to Hl CO to Hl 0 Q P O 4 Oct. to to o co 9 Sept. . . co O CO * VO 2 Aug. . . OX 5 to Cn to •oo to 9 June .. Hl to Date of Sowing. 1 4x *d o CO vo o CO Ox vO to O' vO to Cn co M -tx vO M ■d to ib P E vo to _g) 00 oo Cn "oo co "o> Cn O' 00 'o Cn CO co to OO co Cn O *Ox vo o o Percentage of Plants matiirArl. co 6 0 M c * tn CD - * x x > y op * : - 3 K- ■ CD P Cn 6 6 6 6 Cn ■"4 to 6 Cn Cn Cn Oi 6 6 6 d 6 Cn 6 y O 00 «<J vo o bo M to CO o o nx tjl M Cn c n bo Total. n Cn. Co O' 0 O' “4 VO H> *4 Ch Ox O 00 to VO vO o o •3 3 w to to Cn CO to O 5 co to to w to CO Ox |x co Smutted. p" O co vO Ox vO Cn Cn Cn o to to O' OO 00 "4 o co co ►S to 0 B’ * * •bg-« . to •ij to O to Ox "o to to to to co to to to to to to to o to co Percentage smutted. CD aq y o X io to E H xo '/ Co Cn Cn to 6 Cn 6 6 to oo co to co co 6 -A HI 6 co to 00 kO 00 oo Co *oo Cn co "ox Cn O' Ch CO <0 Cn CO co to 00 Cn VO "ox 4iJ vO vO O Percentage of Plants mat.iTrp.rL p, 0 s <T\ nx co Cn nx co ■<! rrx K<J GX [X [-■ Ch Hx 00 oo v£) o Total. cd Co o -4 vO - [s. o co VO o - [\ H < Ox v n o 00 nx *%4 Cx) cn Cn co Cn 00 Cn 4* 00 o H* to oo HI to to o co 1 K ( n to co vO Cn Jx to to d o 00 K <0 M J—l ( n to Smutted. Ch to Cn O' to o "4 o co Cn to O to CO Ox P* 6 to CD P ’ Cn 6 6 6 6 Cn *-4 to 6 Cn Cn Cn Cn 6 6 0 6 6 sn Cn 6 y Hi Hf H| o oo vO o 00 M to co 0 0 Ch Cn *d HI Cn -■[X Cn CO Total. n Cn Co Ox o Ox *“4 “*4 vO O' Ch 0 CO to VO VO 0 O hj o oo to to vO to vO to o J4 Cn co cO bo Ox Ox co Cn to Percentage smutted. • 4* CO o VO O to o HI o CO -h. VO Ox Cn O H co CO o CO HI M to to t xl to )_( to M to to H to -4 w 1— < o UJ Ox o co Ox vO to Ox cO to cn oo -T--M 4 O > : o - ** cd" > s 0Q : *• : B t P to ct> X 4 d> P S; p o p OQ CD cn Cn Ox Cn "oo "tb £ M 4*. io "o o Mean TerniicD 8 6 00 co CO O'. l-H 6 6 6 vo VO V0 6 O' Ui perature. o o - sd i— < o n o o o o o o o o o o O o o o o o o o x o § Total Ox o o o o to o o co CO to to o o o co to Ox O' CO 2 O' o Rainfall. to to o o vo co Cn o O' Ox H H MJ 4* O 4 >. to “ |S CO HI to to Cn Co to CO CO to to w H| to Co _|s Co I Smutted. p* y o vO C' vO Cn Cn Cn o to to Ox CO 00 *<* •M 0 co CO .. •* CO C/2 y CO to o to to Ch U CO O to to to to to co to to to -2 to to CO -to to 0 00 Percentage to to Co Cn Cn to o Cn o o to co CO to co CO 0 0 co? £ Ox Ox co I JI Ch 00 o ><1 Ch •s<J fS ■ |S cn (T\ CO CO VO 0: ox CO >— 1 kO o 00 CJ) O 4x -|x HI Ch cn’ 0 OO Co ■ Total. O C/1 CO -£■ Cn CO Cn -t* CO vO w to 00 w to to 0 00 w 1 K to co vO Cn to Co 0 0 co 4x vO [S HI Cn to Smutted. CD P C-7X to H Cn -k Ch to o .0 Co Cn to . K 0 to CO Ch Pox to O to Cn w to 5 to o M Cn OO <D co Ch Ch CO Cn to Percentage CO co o VO o to O H o 00 CD Ox Cn 0 CO CO 0 00 HI to to HI CO to HI to HI H( to to H CO to ; H( Hi H *d o CO Ch o CO Ch c0 to Ox VO to cn 00 F—i 4* H •d 0 ? ■ ■ > : o *• - tn cd ►0 - * > y op x £ * y : : f P K> CD X* • 6 ' P shbur 0 . Cu ; j ! Ct" . ■ 0 P WP \ ffQ........ CD 2 0 Cn Cn Ch CO Cn £ *O\ ■fe io D £ £ co CO io "o O> £ <0 V© ■ Mean Temteorc rds. . 6 CO CO Co Ox *d Cn VO H 0 vO' vO >O vO •H Cn kO O O' cn CO •d H . perature. 0 1— 1 ?3. o o Hi o O o o o o 0 O O O O 0 0 0 O O 0 0 0 0 0 ■ Total n o o o to o o CO Co to to O O 0 co to Ch Ox 00 0 Ox 0 ■ Rainfall. to to o 0 v© co ■d Cn 4x O Ox O' H M vO 0 4*
Table 7. Incidence of Loose Smut in relation to Date of Sowing.
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Bibliographic details
New Zealand Journal of Agriculture, Volume XXX, Issue 3, 20 March 1925, Page 167
Word Count
4,304LOOSE SMUT OF WHEAT. New Zealand Journal of Agriculture, Volume XXX, Issue 3, 20 March 1925, Page 167
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