Vol. 15â1961 - NorthEastern Weed Science Society
Vol. 15â1961 - NorthEastern Weed Science Society Vol. 15â1961 - NorthEastern Weed Science Society
within three inches of the soIl surface. Mature seeds scattered on the soil surface in the tall, produced seedlings the following spring. The average number of seeds per berry on mature plants in this study was 86 with a range of II to 189. RESULTSANDDISCUSSION: seed Germination Tests A number of Borse nettle seed emergence tests I carried out in the greenhouse and in the field, had indicated the high potential of the weed to spread by seed. To determine the factors influencing germination under more closely controlled conditiOns, tests were conducted at the Division of Seed Investigations, New York State Agricultural ~peri.ment Station at Qeneva. The tests included investigations of the influence on germ.1nation of temperature treatments, substrate moisten1r.lg agellts, weight of' seed, and light. Summaryof Seed Germination Tests In seed germination tests, the treatment of 20 to 30 degrees C. alternating temperatures (20 degrees C. for 15 hours, 30 degrees C. for 9 hours) us ing either tap water or 0.2 per cent solution ot potassium nitrate as the substrate nlo:J.stening agent, proVided the most favorable conditions for germination. The highest germination obllained under these conditions was 70 per cent. Relatively good germ.1natipn..was also obtained using: (a) 10 to 30 degrees C. alternating temperatures, (b) 20 degrees C. constant temperature with potass 1umnitrate, and (0) 30 degrees C.constant temperature With potassium nitrate. 'L1sht did not appear to be necessary for seed g~rm.1nation, but exposure of seed to light tends to increase the germination rate 1n the early stages ot the germination period. Heavier seed had a higher germination percentage than light seed. Root, Stem, and Flower Studies Horse nettle is readily propagated by means ot the underground parts ot the plant. several experiments were conducted to determine the characteristics of these structures and the effects of certa.1n cultural practices on reproduction from these parts. Studies were also made concerning flower and berry production by Horse nettle plants and the effects of cultural practices on their for 'mation. :rnvestigations were made of: (&)the kinds of underground structures involved in reproduction, (b) vegetatbereproduct1on from root cuttings obtained trom various depths in the SOil, (c) the influence of size of root cutting on reproduction, (d) the numbers of flowers and berries produced, (e) the growth characteristics of plants obtained from several locations in New York State, (f) the 'influence of depth of plantiDg and length of drying ot underground structures on reproduction, and (g) the effects of frequency ot cutting on plant suTv1va.1, rate of growth, seed production, and character ot growth.
339. Summaryof Root, Stem, and Flo~r Studies No rhizome production was observed in any of the Horse nettle plants studied. New shoots, developing from the underground parts of the plant, appeared to start from adventitious buds produced at irregular intervals and at unpredictable locations along the roots. Tap roots, grOWing at a depth down to 112 centimeters in the field, when .. ' excavated, cut into sections, and planted in soil, produced new shoots from adventitious buds. Horse nettle was capable of reproducing vegetatively from very small root cuttings less than one inch long and 3/l6ths of an inch in diameter. Under greenhouse conditions in: woodenf'lats, Horse nettle plants grown from root cuttings and 'seed thepre\rious year, produced 9.3 and 10.1 new shoots, respectively. Established Horse nettle plants, grown from seed the previous year, produced an average of 2.5 new shoots per plant in outdoor 2 x 2 foot concrete frames having no artificial depth restrictions on root development. These observations suggest that Horse nettle plants grown in soils which restrict normal root development may produce a larger number of plal ts from buds than roots in soils permitting deep root penetration. No significant differences were observed in the growth habit of plants g l'.cMnin the greenhouse from root cuttings obtained from several different locations 1n NewYork State. Root cuttings of Horse nettle plants produced new shoots when planted as deep as 18 inches in well drained, friable silt loam soil. Therefore, no appreciable reduction in Horse nettle production could be expected as a result of deep tillage operations. Root cuttings exposed to drying on the soil surface for three days or longer, did not develop shoots when planted at two-inch depths in soil. Thus, Horse nettle roots lose their viability after being exposed to relatively short periods of drying on the soil surface. Of 92 root cuttings planted at 1-1/2 to 2-inch depths, 91 (99 per cent) produced at least one plant and averaged 1.2 plants per cutting. This illustrates the high reproductive capacity of this plant from vegetative parts. There was no mortality among Horse nettle plants grown from root cuttings that were clipped at a 2-1/2-inch height, at 5- to 8-day intervals throughout a single grOWing season. Seed production was almost entire.ly prevented. -- Based on these results) the most appropriate time to clip Horse nettle plants to prevent the production of viable seed, is in mid-July and again in mid-August. It would be desirable to make further germination studies of seed harvested during the various stages of growth of plants grown from seed and from roots so that more reliable clipping schedules could be made.
- Page 287 and 288: 287. Halts F-24, Halts F-26, Halts
- Page 289 and 290: POST-.EJ.iEhGENCE CONThOLOF CIiABGI
- Page 291 and 292: ,veedone at 4 pounds of tL.cl per a
- Page 293 and 294: ( ( ( Table I. Post-Emergence Contr
- Page 295 and 296: • •• ., .. • •• ',' •
- Page 297 and 298: 297. compatible with grub-proofing
- Page 299 and 300: 299, Diphenatrile Results During th
- Page 301 and 302: 301. tentative generic name triflur
- Page 303 and 304: - 1 PRE-ENERGENCE CRABGRASS CONTROL
- Page 305 and 306: Discussion 30; • a) Pre-emergence
- Page 307 and 308: 307. TABLEI -- Comparison of Produc
- Page 309 and 310: -' Table II (can't) 309. Stand of S
- Page 312 and 313: 312. THEEFFECTIVENESSOF COMBINATION
- Page 314 and 315: 314. Table 2. Stand Counts and Sile
- Page 316 and 317: 316. planted control before these h
- Page 318 and 319: Table II. The control of quackgrass
- Page 320 and 321: 320. growing season in the 1957-59
- Page 322 and 323: 322. Table I Main Effects of Cultur
- Page 324 and 325: 324. Atrazine by September 10 when
- Page 326 and 327: 326. Another effect of Atrazine tha
- Page 328 and 329: 32S. Amitrol-T was intermediate in
- Page 330 and 331: Qolumn Separation: Cellulose. A 24
- Page 332 and 333: 332, Figure -I. Chromatogram of qua
- Page 334 and 335: 334. PRELIMINARYRESULTSONTHE USE OF
- Page 336 and 337: 336. DATEOF BERRYHARVESTAS IT AFFEC
- Page 340 and 341: 340 .. The growth ra.te of Horse ne
- Page 342 and 343: 342. dish containing ten seeds bet\
- Page 344 and 345: 344. is not a factor in in It is
- Page 346 and 347: 346 • .Absornt:j.Qn Qn Exchange R
- Page 348 and 349: 348. The' chrona tog ram."WaS first
- Page 350 and 351: 350. PROGRESSREPORTON A STUDYOF THE
- Page 352 and 353: 352. 7. Fluctuating warm and cold w
- Page 354 and 355: 354. A clos.e correlation was found
- Page 356 and 357: 356. 1 THE ANATOMICAL NATUREO:BTHE
- Page 358 and 359: 358. The 2,4,5-TP was most effectiv
- Page 360 and 361: Table I. Effect. of Pre-emergence T
- Page 362 and 363: INTRODUCIIOB: THEEFFECTOF WEEDCOMPE
- Page 364 and 365: 1";. 1958 JFab1e I (cont ' d) Treat
- Page 366 and 367: 366. fiE USE OF FENACFOR QUACKGRASS
- Page 368 and 369: 36$. SUMMARY: Based on a I).umber o
- Page 370 and 371: - Table 1. Chemicals and Rates Used
- Page 372 and 373: 372. On spring plowed plots I where
- Page 374 and 375: Table 1. Treat.ments Used and Stand
- Page 376 and 377: 37t. PRELIMINARYRESULTSONTHE CONTRO
- Page 378 and 379: 378. CHEMICAL TREATMENTS FORTHECONT
- Page 380 and 381: Table ;. Visual RatiDgs and Stand C
- Page 382 and 383: ANN11AL WEEDCONTROL IN SILAGECORN1
- Page 384 and 385: TABLEI. field Corn tiead Control an
- Page 386 and 387: Sunderiand,' Mass..Experiment: In t
within three<br />
inches of the soIl surface.<br />
Mature seeds scattered on the soil surface in the tall, produced seedlings<br />
the following spring.<br />
The average number of seeds per berry on mature plants in this study was 86<br />
with a range of II to 189.<br />
RESULTSANDDISCUSSION:<br />
seed Germination Tests<br />
A number of Borse nettle seed emergence tests I carried out in the greenhouse<br />
and in the field, had indicated the high potential of the weed to spread by seed.<br />
To determine the factors influencing germination under more closely controlled<br />
conditiOns, tests were conducted at the Division of Seed Investigations, New<br />
York State Agricultural ~peri.ment Station at Qeneva. The tests included<br />
investigations of the influence on germ.1nation of temperature treatments,<br />
substrate moisten1r.lg agellts, weight of' seed, and light.<br />
Summaryof Seed Germination Tests<br />
In seed germination tests, the treatment of 20 to 30 degrees C. alternating<br />
temperatures (20 degrees C. for 15 hours, 30 degrees C. for 9 hours) us ing<br />
either tap water or 0.2 per cent solution ot potassium nitrate as the substrate<br />
nlo:J.stening agent, proVided the most favorable conditions for germination. The<br />
highest germination obllained under these conditions was 70 per cent. Relatively<br />
good germ.1natipn..was also obtained using: (a) 10 to 30 degrees C. alternating<br />
temperatures, (b) 20 degrees C. constant temperature with potass 1umnitrate,<br />
and (0) 30 degrees C.constant temperature With potassium nitrate.<br />
'L1sht did not appear to be necessary for seed g~rm.1nation, but exposure of<br />
seed to light tends to increase the germination rate 1n the early stages ot the<br />
germination period.<br />
Heavier seed had a higher germination percentage than light seed.<br />
Root, Stem, and Flower Studies<br />
Horse nettle is readily propagated by means ot the underground parts ot the<br />
plant. several experiments were conducted to determine the characteristics of<br />
these structures and the effects of certa.1n cultural practices on reproduction<br />
from these parts. Studies were also made concerning flower and berry production<br />
by Horse nettle plants and the effects of cultural practices on their for<br />
'mation.<br />
:rnvestigations were made of: (&)the kinds of underground structures involved<br />
in reproduction, (b) vegetatbereproduct1on from root cuttings obtained trom<br />
various depths in the SOil, (c) the influence of size of root cutting on reproduction,<br />
(d) the numbers of flowers and berries produced, (e) the growth characteristics<br />
of plants obtained from several locations in New York State, (f)<br />
the 'influence of depth of plantiDg and length of drying ot underground structures<br />
on reproduction, and (g) the effects of frequency ot cutting on plant suTv1va.1,<br />
rate of growth, seed production, and character ot growth.
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